From 5695d130678a842f40b81c47e2848a0d15edc884 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 24 Sep 2024 19:16:10 +0900
Subject: [PATCH 01/51] 217 / Contains Duplicate / Easy / 12m

---
 oh-chaeyeon/217_Contains_Duplicate.js | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)
 create mode 100644 oh-chaeyeon/217_Contains_Duplicate.js

diff --git a/oh-chaeyeon/217_Contains_Duplicate.js b/oh-chaeyeon/217_Contains_Duplicate.js
new file mode 100644
index 0000000..f3b462e
--- /dev/null
+++ b/oh-chaeyeon/217_Contains_Duplicate.js
@@ -0,0 +1,16 @@
+/**
+ * @param {number[]} nums
+ * @return {boolean}
+ */
+var containsDuplicate = function (nums) {
+  const seen = new Set();
+
+  for (let num of nums) {
+    if (seen.has(num)) {
+      return true;
+    }
+    seen.add(num);
+  }
+
+  return false;
+};

From 9b2a2df6948e186b05181d3a0bb7dbe4e13680c4 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 24 Sep 2024 19:29:52 +0900
Subject: [PATCH 02/51] 268 / Missing number / Easy / 10m

---
 oh-chaeyeon/268_Missing_number.js | 15 +++++++++++++++
 1 file changed, 15 insertions(+)
 create mode 100644 oh-chaeyeon/268_Missing_number.js

diff --git a/oh-chaeyeon/268_Missing_number.js b/oh-chaeyeon/268_Missing_number.js
new file mode 100644
index 0000000..5ffc0ca
--- /dev/null
+++ b/oh-chaeyeon/268_Missing_number.js
@@ -0,0 +1,15 @@
+/**
+ * @param {number[]} nums
+ * @return {number}
+ */
+var missingNumber = function (nums) {
+  const n = nums.length;
+  const totalSum = (n * (n + 1)) / 2;
+
+  let numsSum = 0;
+  for (let num of nums) {
+    numsSum += num;
+  }
+
+  return totalSum - numsSum;
+};

From a20252eff05b69e13f5c6b7983f78174a11ae595 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 24 Sep 2024 20:13:47 +0900
Subject: [PATCH 03/51] 121 / Best Time to buy and sell stock / Easy / 32m

---
 .../121_Best_Time_to_buy_and_sell_stock.js    | 21 +++++++++++++++++++
 1 file changed, 21 insertions(+)
 create mode 100644 oh-chaeyeon/121_Best_Time_to_buy_and_sell_stock.js

diff --git a/oh-chaeyeon/121_Best_Time_to_buy_and_sell_stock.js b/oh-chaeyeon/121_Best_Time_to_buy_and_sell_stock.js
new file mode 100644
index 0000000..6f13172
--- /dev/null
+++ b/oh-chaeyeon/121_Best_Time_to_buy_and_sell_stock.js
@@ -0,0 +1,21 @@
+/**
+ * @param {number[]} prices
+ * @return {number}
+ */
+var maxProfit = function (prices) {
+  let minValue = Infinity;
+  let maxProfit = 0;
+
+  for (let i = 0; i < prices.length; i++) {
+    if (prices[i] < minValue) {
+      minValue = prices[i];
+    } else {
+      const profit = prices[i] - minValue;
+      if (profit > maxProfit) {
+        maxProfit = profit;
+      }
+    }
+  }
+
+  return maxProfit;
+};

From 8f136a5b51373e013f3a65919afbde45e0d404db Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 24 Sep 2024 20:38:18 +0900
Subject: [PATCH 04/51] 253 / Meeting Rooms / Easy / 20m

---
 oh-chaeyeon/253_Meeting_Rooms.js | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)
 create mode 100644 oh-chaeyeon/253_Meeting_Rooms.js

diff --git a/oh-chaeyeon/253_Meeting_Rooms.js b/oh-chaeyeon/253_Meeting_Rooms.js
new file mode 100644
index 0000000..33a3916
--- /dev/null
+++ b/oh-chaeyeon/253_Meeting_Rooms.js
@@ -0,0 +1,23 @@
+/**
+ * Definition of Interval:
+ * class Interval {
+ *   constructor(start, end) {
+ *     this.start = start;
+ *     this.end = end;
+ *   }
+ * }
+ */
+
+class Solution {
+  canAttendMeetings(intervals) {
+    intervals.sort((a, b) => a.start - b.start);
+
+    for (let i = 0; i < intervals.length - 1; i++) {
+      if (intervals[i].end > intervals[i + 1].start) {
+        return false;
+      }
+    }
+
+    return true;
+  }
+}

From 3024e5376c4900aa637598f2919092df7a6921ee Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 24 Sep 2024 21:18:41 +0900
Subject: [PATCH 05/51] 15 / 3Sum / Medium / 22m

---
 oh-chaeyeon/15_3Sum.js | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)
 create mode 100644 oh-chaeyeon/15_3Sum.js

diff --git a/oh-chaeyeon/15_3Sum.js b/oh-chaeyeon/15_3Sum.js
new file mode 100644
index 0000000..f360bc5
--- /dev/null
+++ b/oh-chaeyeon/15_3Sum.js
@@ -0,0 +1,33 @@
+/**
+ * @param {number[]} nums
+ * @return {number[][]}
+ */
+var threeSum = function (nums) {
+  const result = [];
+  nums.sort((a, b) => a - b);
+
+  for (let i = 0; i < nums.length - 2; i++) {
+    if (i > 0 && nums[i] === nums[i - 1]) continue;
+
+    let left = i + 1;
+    let right = nums.length - 1;
+
+    while (left < right) {
+      const sum = nums[i] + nums[left] + nums[right];
+      if (sum === 0) {
+        result.push([nums[i], nums[left], nums[right]]);
+
+        while (left < right && nums[left] === nums[left + 1]) left++;
+        while (left < right && nums[right] === nums[right - 1]) right--;
+
+        left++;
+        right--;
+      } else if (sum < 0) {
+        left++;
+      } else {
+        right--;
+      }
+    }
+  }
+  return result;
+};

From ed4b872c1f7fdd7174141d9b4000929e82cb158a Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 24 Sep 2024 21:58:54 +0900
Subject: [PATCH 06/51] =?UTF-8?q?252=20/=20Meeting=20Rooms=20/=20Easy=20/?=
 =?UTF-8?q?=2020m=20(=EB=AC=B8=EC=A0=9C=EB=B2=88=ED=98=B8=20=EC=88=98?=
 =?UTF-8?q?=EC=A0=95)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 oh-chaeyeon/{253_Meeting_Rooms.js => 252_Meeting_Rooms.js} | 0
 1 file changed, 0 insertions(+), 0 deletions(-)
 rename oh-chaeyeon/{253_Meeting_Rooms.js => 252_Meeting_Rooms.js} (100%)

diff --git a/oh-chaeyeon/253_Meeting_Rooms.js b/oh-chaeyeon/252_Meeting_Rooms.js
similarity index 100%
rename from oh-chaeyeon/253_Meeting_Rooms.js
rename to oh-chaeyeon/252_Meeting_Rooms.js

From 53a320d142927579cacdd8250246328df24e8e26 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 1 Oct 2024 19:23:37 +0900
Subject: [PATCH 07/51] 242 / Valid Anagram / Easy / 11m

---
 oh-chaeyeon/242_Valid_Anagram.js | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)
 create mode 100644 oh-chaeyeon/242_Valid_Anagram.js

diff --git a/oh-chaeyeon/242_Valid_Anagram.js b/oh-chaeyeon/242_Valid_Anagram.js
new file mode 100644
index 0000000..4e30dc4
--- /dev/null
+++ b/oh-chaeyeon/242_Valid_Anagram.js
@@ -0,0 +1,20 @@
+/**
+ * @param {string} s
+ * @param {string} t
+ * @return {boolean}
+ */
+var isAnagram = function (s, t) {
+  if (s.length != t.length) return false;
+
+  let countMap = {};
+  for (let char of s) {
+    countMap[char] = (countMap[char] || 0) + 1;
+  }
+
+  for (let char of t) {
+    if (!countMap[char]) return false;
+    countMap[char]--;
+  }
+
+  return true;
+};

From c4a58be6756dd02d938af78998d457d291469b1e Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 1 Oct 2024 19:39:12 +0900
Subject: [PATCH 08/51] 238 / Product of Arrays Except Self / Medium / 14m

---
 .../238_Product_of_Arrays_Except_Self.js      | 22 +++++++++++++++++++
 1 file changed, 22 insertions(+)
 create mode 100644 oh-chaeyeon/238_Product_of_Arrays_Except_Self.js

diff --git a/oh-chaeyeon/238_Product_of_Arrays_Except_Self.js b/oh-chaeyeon/238_Product_of_Arrays_Except_Self.js
new file mode 100644
index 0000000..17f1623
--- /dev/null
+++ b/oh-chaeyeon/238_Product_of_Arrays_Except_Self.js
@@ -0,0 +1,22 @@
+/**
+ * @param {number[]} nums
+ * @return {number[]}
+ */
+var productExceptSelf = function (nums) {
+  const n = nums.length;
+  const answer = new Array(n).fill(1);
+
+  let left = 1;
+  for (let i = 0; i < n; i++) {
+    answer[i] = left;
+    left *= nums[i];
+  }
+
+  let right = 1;
+  for (let i = n - 1; i >= 0; i--) {
+    answer[i] *= right;
+    right *= nums[i];
+  }
+
+  return answer;
+};

From fd63ce556a1d7c35d26e0f9d68debcb2131205d5 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 1 Oct 2024 19:54:14 +0900
Subject: [PATCH 09/51] 191 / Number of 1 Bits / Easy / 14m

---
 oh-chaeyeon/191_Number_of _1_Bits.js | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)
 create mode 100644 oh-chaeyeon/191_Number_of _1_Bits.js

diff --git a/oh-chaeyeon/191_Number_of _1_Bits.js b/oh-chaeyeon/191_Number_of _1_Bits.js
new file mode 100644
index 0000000..e40dfbb
--- /dev/null
+++ b/oh-chaeyeon/191_Number_of _1_Bits.js	
@@ -0,0 +1,16 @@
+/**
+ * @param {number} n
+ * @return {number}
+ */
+var hammingWeight = function (n) {
+  const num = n.toString(2);
+  let count = 0;
+
+  for (let char of num) {
+    if (char === "1") {
+      count++;
+    }
+  }
+
+  return count;
+};

From fea74058e4552e67425e34c22b412b38fe252a1a Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 1 Oct 2024 20:07:21 +0900
Subject: [PATCH 10/51] 100 / Same Tree / Easy / 12m

---
 oh-chaeyeon/100_Same_Tree.js | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)
 create mode 100644 oh-chaeyeon/100_Same_Tree.js

diff --git a/oh-chaeyeon/100_Same_Tree.js b/oh-chaeyeon/100_Same_Tree.js
new file mode 100644
index 0000000..37b5b14
--- /dev/null
+++ b/oh-chaeyeon/100_Same_Tree.js
@@ -0,0 +1,28 @@
+/**
+ * Definition for a binary tree node.
+ * function TreeNode(val, left, right) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.left = (left===undefined ? null : left)
+ *     this.right = (right===undefined ? null : right)
+ * }
+ */
+/**
+ * @param {TreeNode} p
+ * @param {TreeNode} q
+ * @return {boolean}
+ */
+var isSameTree = function (p, q) {
+  if (p === null && q === null) {
+    return true;
+  }
+
+  if (p === null || q === null) {
+    return false;
+  }
+
+  if (p.val !== q.val) {
+    return false;
+  }
+
+  return isSameTree(p.left, q.left) && isSameTree(p.right, q.right);
+};

From ff58ada99772cbabc888fd1e185866458632046f Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 1 Oct 2024 21:50:29 +0900
Subject: [PATCH 11/51] 746 / Min Cost Climbing Stairs / Easy / 50m

---
 oh-chaeyeon/746_Min_Cost_Climbing_Stairs.js | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)
 create mode 100644 oh-chaeyeon/746_Min_Cost_Climbing_Stairs.js

diff --git a/oh-chaeyeon/746_Min_Cost_Climbing_Stairs.js b/oh-chaeyeon/746_Min_Cost_Climbing_Stairs.js
new file mode 100644
index 0000000..f6c1d79
--- /dev/null
+++ b/oh-chaeyeon/746_Min_Cost_Climbing_Stairs.js
@@ -0,0 +1,17 @@
+/**
+ * @param {number[]} cost
+ * @return {number}
+ */
+var minCostClimbingStairs = function (cost) {
+  const n = cost.length;
+  const minCost = new Array(n + 1).fill(0);
+
+  minCost[0] = 0;
+  minCost[1] = cost[0];
+
+  for (let i = 2; i <= n; i++) {
+    minCost[i] = cost[i - 1] + Math.min(minCost[i - 1], minCost[i - 2]);
+  }
+
+  return Math.min(minCost[n], minCost[n - 1]);
+};

From 7735104186bafdcd2c200477db2526b683a0a87d Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Wed, 9 Oct 2024 03:12:28 +0900
Subject: [PATCH 12/51] 49 / Group Anagrams / Medium / 43m

---
 oh-chaeyeon/49_Group_Anagrams.js | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)
 create mode 100644 oh-chaeyeon/49_Group_Anagrams.js

diff --git a/oh-chaeyeon/49_Group_Anagrams.js b/oh-chaeyeon/49_Group_Anagrams.js
new file mode 100644
index 0000000..5cb274c
--- /dev/null
+++ b/oh-chaeyeon/49_Group_Anagrams.js
@@ -0,0 +1,27 @@
+/**
+ * @param {string[]} strs
+ * @return {string[][]}
+ */
+var groupAnagrams = function (strs) {
+  const map = new Map();
+
+  for (let str of strs) {
+    const count = new Array(26).fill(0);
+
+    for (let char of str) {
+      count[char.charCodeAt(0) - "a".charCodeAt(0)]++;
+    }
+
+    const key = count.join("#");
+
+    if (map.has(key)) {
+      map.get(key).push(str);
+    } else {
+      map.set(key, [str]);
+    }
+  }
+  return Array.from(map.values());
+};
+
+// Runtime : 117ms
+// Memory : 63.07MB

From 84ca09359e8d70827e81fdfb6532a92de202134b Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Wed, 9 Oct 2024 03:13:19 +0900
Subject: [PATCH 13/51] 190 / Reverse Bits / Easy / 33m

---
 oh-chaeyeon/190_Reverse_Bits.js | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)
 create mode 100644 oh-chaeyeon/190_Reverse_Bits.js

diff --git a/oh-chaeyeon/190_Reverse_Bits.js b/oh-chaeyeon/190_Reverse_Bits.js
new file mode 100644
index 0000000..713c14d
--- /dev/null
+++ b/oh-chaeyeon/190_Reverse_Bits.js
@@ -0,0 +1,16 @@
+/**
+ * @param {number} n - a positive integer
+ * @return {number} - a positive integer
+ */
+var reverseBits = function (n) {
+  let result = 0;
+  for (let i = 0; i < 32; i++) {
+    result <<= 1;
+    result |= n & 1;
+    n >>>= 1;
+  }
+  return result >>> 0;
+};
+
+// Runtime : 44ms
+// Memory : 50.72MB

From 2acdf2cf688d90cb637763cd6d263e9cd92eff3d Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Wed, 9 Oct 2024 03:14:05 +0900
Subject: [PATCH 14/51] 125 / Valid Palindrome / Easy / 28m

---
 oh-chaeyeon/125_Valid_Palindrome.js | 12 ++++++++++++
 1 file changed, 12 insertions(+)
 create mode 100644 oh-chaeyeon/125_Valid_Palindrome.js

diff --git a/oh-chaeyeon/125_Valid_Palindrome.js b/oh-chaeyeon/125_Valid_Palindrome.js
new file mode 100644
index 0000000..df09d37
--- /dev/null
+++ b/oh-chaeyeon/125_Valid_Palindrome.js
@@ -0,0 +1,12 @@
+/**
+ * @param {string} s
+ * @return {boolean}
+ */
+var isPalindrome = function (s) {
+  let filteredStr = s.toLowerCase().replace(/[^a-z0-9]/g, "");
+  let reversedStr = filteredStr.split("").reverse().join("");
+  return filteredStr === reversedStr;
+};
+
+// Runtime : 58ms
+// Memory : 52.88MB

From 4937727b2705b0583c1e231305c70433c460f898 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Wed, 9 Oct 2024 03:15:22 +0900
Subject: [PATCH 15/51] 322 / Coin Change / Medium / 1h 18m

---
 oh-chaeyeon/322_Coin_Change.js | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)
 create mode 100644 oh-chaeyeon/322_Coin_Change.js

diff --git a/oh-chaeyeon/322_Coin_Change.js b/oh-chaeyeon/322_Coin_Change.js
new file mode 100644
index 0000000..a534aae
--- /dev/null
+++ b/oh-chaeyeon/322_Coin_Change.js
@@ -0,0 +1,20 @@
+/**
+ * @param {number[]} coins
+ * @param {number} amount
+ * @return {number}
+ */
+var coinChange = function (coins, amount) {
+  const dp = new Array(amount + 1).fill(Infinity);
+  dp[0] = 0;
+
+  for (let coin of coins) {
+    for (let i = coin; i <= amount; i++) {
+      dp[i] = Math.min(dp[i], dp[i - coin] + 1);
+    }
+  }
+
+  return dp[amount] === Infinity ? -1 : dp[amount];
+};
+
+// Runtime : 83ms
+// Memory : 53.06MB

From 2daaa4c791afe2dfde8f716843c64b7311d4831a Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Wed, 9 Oct 2024 03:16:04 +0900
Subject: [PATCH 16/51] 206 / Reverse Linked list / Easy / 27m

---
 oh-chaeyeon/206_Reverse_Linked_list.js | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)
 create mode 100644 oh-chaeyeon/206_Reverse_Linked_list.js

diff --git a/oh-chaeyeon/206_Reverse_Linked_list.js b/oh-chaeyeon/206_Reverse_Linked_list.js
new file mode 100644
index 0000000..88c9237
--- /dev/null
+++ b/oh-chaeyeon/206_Reverse_Linked_list.js
@@ -0,0 +1,26 @@
+/**
+ * Definition for singly-linked list.
+ * function ListNode(val, next) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.next = (next===undefined ? null : next)
+ * }
+ */
+/**
+ * @param {ListNode} head
+ * @return {ListNode}
+ */
+var reverseList = function (head) {
+  let prev = null;
+
+  while (head) {
+    let temp = head.next;
+    head.next = prev;
+    prev = head;
+    head = temp;
+  }
+
+  return prev;
+};
+
+// Runtime : 62ms
+// Memory : 50.97MB

From 64fd3b5b7ecda2af23632353e3d1eac90ea8413f Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 15 Oct 2024 22:41:49 +0900
Subject: [PATCH 17/51] 1 / Two Sum / Easy / 15m 55s

---
 oh-chaeyeon/1_Two_Sum.js | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)
 create mode 100644 oh-chaeyeon/1_Two_Sum.js

diff --git a/oh-chaeyeon/1_Two_Sum.js b/oh-chaeyeon/1_Two_Sum.js
new file mode 100644
index 0000000..1976a78
--- /dev/null
+++ b/oh-chaeyeon/1_Two_Sum.js
@@ -0,0 +1,19 @@
+/**
+ * @param {number[]} nums
+ * @param {number} target
+ * @return {number[]}
+ */
+var twoSum = function (nums, target) {
+  let map = new Map();
+  for (let i = 0; i < nums.length; i++) {
+    let requiredValue = target - nums[i];
+    if (map.has(requiredValue)) {
+      return [map.get(requiredValue), i];
+    }
+    map.set(nums[i], i);
+  }
+};
+
+// Time taken : 15m 55s
+// Runtime : 51ms
+// Memory : 51.54MB

From 86623d5f89ed829d54f8b1708064677bba23fd49 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 15 Oct 2024 22:42:25 +0900
Subject: [PATCH 18/51] 104 / Maximum Depth of Binary Tree / Easy / 11m 46s

---
 .../104_Maximum_Depth_of_Binary_Tree.js       | 26 +++++++++++++++++++
 1 file changed, 26 insertions(+)
 create mode 100644 oh-chaeyeon/104_Maximum_Depth_of_Binary_Tree.js

diff --git a/oh-chaeyeon/104_Maximum_Depth_of_Binary_Tree.js b/oh-chaeyeon/104_Maximum_Depth_of_Binary_Tree.js
new file mode 100644
index 0000000..a3e1766
--- /dev/null
+++ b/oh-chaeyeon/104_Maximum_Depth_of_Binary_Tree.js
@@ -0,0 +1,26 @@
+/**
+ * Definition for a binary tree node.
+ * function TreeNode(val, left, right) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.left = (left===undefined ? null : left)
+ *     this.right = (right===undefined ? null : right)
+ * }
+ */
+/**
+ * @param {TreeNode} root
+ * @return {number}
+ */
+var maxDepth = function (root) {
+  if (root === null) {
+    return 0;
+  }
+
+  let leftDepth = maxDepth(root.left);
+  let rightDepth = maxDepth(root.right);
+
+  return Math.max(leftDepth, rightDepth) + 1;
+};
+
+// Time taken : 11m 46s
+// Runtime : 59ms
+// Memory : 51.59MB

From 2831c872116395b351efa0088cc52679995f22cd Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 15 Oct 2024 22:42:52 +0900
Subject: [PATCH 19/51] 141 / Linked List Cycle / Easy / 37m 26s

---
 oh-chaeyeon/141_Linked_List_Cycle.js | 30 ++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)
 create mode 100644 oh-chaeyeon/141_Linked_List_Cycle.js

diff --git a/oh-chaeyeon/141_Linked_List_Cycle.js b/oh-chaeyeon/141_Linked_List_Cycle.js
new file mode 100644
index 0000000..bd371ed
--- /dev/null
+++ b/oh-chaeyeon/141_Linked_List_Cycle.js
@@ -0,0 +1,30 @@
+/**
+ * Definition for singly-linked list.
+ * function ListNode(val) {
+ *     this.val = val;
+ *     this.next = null;
+ * }
+ */
+
+/**
+ * @param {ListNode} head
+ * @return {boolean}
+ */
+var hasCycle = function (head) {
+  let visited = new Set();
+  let current = head;
+
+  while (current !== null) {
+    if (visited.has(current)) {
+      return true;
+    }
+    visited.add(current);
+    current = current.next;
+  }
+
+  return false;
+};
+
+// Time taken : 37m 26s
+// Runtime : 67ms
+// Memory : 52.91MB

From f86608ebada6830c8e067f5e77028cd4047b2b5d Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 15 Oct 2024 22:43:14 +0900
Subject: [PATCH 20/51] 202 /Happy Number / Easy / 20m 6s

---
 oh-chaeyeon/202_Happy_Number.js | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)
 create mode 100644 oh-chaeyeon/202_Happy_Number.js

diff --git a/oh-chaeyeon/202_Happy_Number.js b/oh-chaeyeon/202_Happy_Number.js
new file mode 100644
index 0000000..e8b03f3
--- /dev/null
+++ b/oh-chaeyeon/202_Happy_Number.js
@@ -0,0 +1,24 @@
+/**
+ * @param {number} n
+ * @return {boolean}
+ */
+var isHappy = function (n) {
+  const record = new Set();
+
+  while (n !== 1) {
+    if (record.has(n)) {
+      return false;
+    }
+    record.add(n);
+
+    n = n
+      .toString()
+      .split("")
+      .reduce((sum, digit) => sum + digit * digit, 0);
+  }
+  return true;
+};
+
+// Time taken : 20m 6s
+// Runtime : 55ms
+// Memory : 50.80MB

From e0fccd7d35004ce80a971d6818ed4bf87091f3bd Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 15 Oct 2024 22:43:36 +0900
Subject: [PATCH 21/51] 20 / Valid Parentheses / Easy / 18m 24s

---
 oh-chaeyeon/20_Valid_Parentheses.js | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)
 create mode 100644 oh-chaeyeon/20_Valid_Parentheses.js

diff --git a/oh-chaeyeon/20_Valid_Parentheses.js b/oh-chaeyeon/20_Valid_Parentheses.js
new file mode 100644
index 0000000..15ecd2e
--- /dev/null
+++ b/oh-chaeyeon/20_Valid_Parentheses.js
@@ -0,0 +1,29 @@
+/**
+ * @param {string} s
+ * @return {boolean}
+ */
+var isValid = function (s) {
+  const stack = [];
+  const map = {
+    "(": ")",
+    "{": "}",
+    "[": "]",
+  };
+
+  for (let char of s) {
+    if (char in map) {
+      stack.push(char);
+    } else {
+      const last = stack.pop();
+      if (map[last] !== char) {
+        return false;
+      }
+    }
+  }
+
+  return stack.length === 0;
+};
+
+// Time taken : 18m 24s
+// Runtime : 55ms
+// Memory : 50.87MB

From 61753aaeae4dacbacc732b3cec202e78d98a4834 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 22 Oct 2024 22:43:39 +0900
Subject: [PATCH 22/51] 338 / Counting Bits / Easy / 16m

---
 oh-chaeyeon/338_Counting_Bits.js | 15 +++++++++++++++
 1 file changed, 15 insertions(+)
 create mode 100644 oh-chaeyeon/338_Counting_Bits.js

diff --git a/oh-chaeyeon/338_Counting_Bits.js b/oh-chaeyeon/338_Counting_Bits.js
new file mode 100644
index 0000000..ee14125
--- /dev/null
+++ b/oh-chaeyeon/338_Counting_Bits.js
@@ -0,0 +1,15 @@
+/**
+ * @param {number} n
+ * @return {number[]}
+ */
+var countBits = function (n) {
+  const bit = new Array(n + 1).fill(0);
+  for (let i = 0; i <= n; i++) {
+    bit[i] = bit[i >> 1] + (i & 1);
+  }
+  return bit;
+};
+
+// Time taken : 16m
+// Runtime : 2ms
+// Memory : 56.14MB

From 47ea9b01e0eabc5c4e8a2910cc4ccdcbe0d30ce5 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 22 Oct 2024 22:44:08 +0900
Subject: [PATCH 23/51] 70 / Climbing Stairs / Easy / 16m 30s

---
 oh-chaeyeon/70_Climbing_Stairs.js | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)
 create mode 100644 oh-chaeyeon/70_Climbing_Stairs.js

diff --git a/oh-chaeyeon/70_Climbing_Stairs.js b/oh-chaeyeon/70_Climbing_Stairs.js
new file mode 100644
index 0000000..57ca9b1
--- /dev/null
+++ b/oh-chaeyeon/70_Climbing_Stairs.js
@@ -0,0 +1,23 @@
+/**
+ * @param {number} n
+ * @return {number}
+ */
+var climbStairs = function (n) {
+  if (n === 1) return 1;
+  if (n === 2) return 2;
+
+  let prev1 = 2;
+  let prev2 = 1;
+
+  for (let i = 3; i <= n; i++) {
+    let current = prev1 + prev2;
+    prev2 = prev1;
+    prev1 = current;
+  }
+
+  return prev1;
+};
+
+// Time taken : 16m 30s
+// Runtime : 0ms
+// Memory : 49.04MB

From f72bab80458d9c93f6d9a5641056930ae13fb7b4 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 22 Oct 2024 22:44:29 +0900
Subject: [PATCH 24/51] 21 / Merge two Sorted Lists / Easy / 40m 32s

---
 oh-chaeyeon/21_Merge_two_Sorted_Lists.js | 70 ++++++++++++++++++++++++
 1 file changed, 70 insertions(+)
 create mode 100644 oh-chaeyeon/21_Merge_two_Sorted_Lists.js

diff --git a/oh-chaeyeon/21_Merge_two_Sorted_Lists.js b/oh-chaeyeon/21_Merge_two_Sorted_Lists.js
new file mode 100644
index 0000000..7976f42
--- /dev/null
+++ b/oh-chaeyeon/21_Merge_two_Sorted_Lists.js
@@ -0,0 +1,70 @@
+//풀이방법1. 두 리스트를 배열로 변환 후 정렬하는 방식
+// Runtime : 4ms
+// Memory : 51.24MB
+/**
+ * Definition for singly-linked list.
+ * function ListNode(val, next) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.next = (next===undefined ? null : next)
+ * }
+ */
+/**
+ * @param {ListNode} list1
+ * @param {ListNode} list2
+ * @return {ListNode}
+ */
+var mergeTwoLists = function (list1, list2) {
+  let arr = [];
+
+  while (list1 !== null) {
+    arr.push(list1.val);
+    list1 = list1.next;
+  }
+
+  while (list2 !== null) {
+    arr.push(list2.val);
+    list2 = list2.next;
+  }
+
+  arr.sort((a, b) => a - b);
+
+  let dummy = new ListNode();
+  let current = dummy;
+
+  for (let val of arr) {
+    current.next = new ListNode(val);
+    current = current.next;
+  }
+
+  return dummy.next;
+};
+
+//풀이방법2. 재귀를 활용한 방식
+// Runtime : 0ms
+// Memory : 52.40MB
+/**
+ * Definition for singly-linked list.
+ * function ListNode(val, next) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.next = (next===undefined ? null : next)
+ * }
+ */
+/**
+ * @param {ListNode} list1
+ * @param {ListNode} list2
+ * @return {ListNode}
+ */
+var mergeTwoLists = function (list1, list2) {
+  if (list1 === null) return list2;
+  if (list2 === null) return list1;
+
+  if (list1.val <= list2.val) {
+    list1.next = mergeTwoLists(list1.next, list2);
+    return list1;
+  } else {
+    list2.next = mergeTwoLists(list1, list2.next);
+    return list2;
+  }
+};
+
+// Time taken : 40m 32s

From d3637a1ca829502809041e126f3fe64bfd03afc4 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 22 Oct 2024 22:44:59 +0900
Subject: [PATCH 25/51] 48 / Rotate Image / Medium / 36m 15s

---
 oh-chaeyeon/48_Rotate_Image.js | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)
 create mode 100644 oh-chaeyeon/48_Rotate_Image.js

diff --git a/oh-chaeyeon/48_Rotate_Image.js b/oh-chaeyeon/48_Rotate_Image.js
new file mode 100644
index 0000000..07b1f43
--- /dev/null
+++ b/oh-chaeyeon/48_Rotate_Image.js
@@ -0,0 +1,21 @@
+/**
+ * @param {number[][]} matrix
+ * @return {void} Do not return anything, modify matrix in-place instead.
+ */
+var rotate = function (matrix) {
+  const n = matrix.length;
+
+  for (let i = 0; i < n; i++) {
+    for (let j = i + 1; j < n; j++) {
+      [matrix[i][j], matrix[j][i]] = [matrix[j][i], matrix[i][j]];
+    }
+  }
+
+  for (let i = 0; i < n; i++) {
+    matrix[i].reverse();
+  }
+};
+
+// Time taken : 36m 15s
+// Runtime : 0ms
+// Memory : 49.28MB

From 91dc0f0561c3cd6d7e2b4ad8b75673aabfb06e28 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 22 Oct 2024 22:45:23 +0900
Subject: [PATCH 26/51] 1046 / Last Stone Weight / Easy / 7m 51s

---
 oh-chaeyeon/1046_Last_Stone_Weight.js | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)
 create mode 100644 oh-chaeyeon/1046_Last_Stone_Weight.js

diff --git a/oh-chaeyeon/1046_Last_Stone_Weight.js b/oh-chaeyeon/1046_Last_Stone_Weight.js
new file mode 100644
index 0000000..1bb55dd
--- /dev/null
+++ b/oh-chaeyeon/1046_Last_Stone_Weight.js
@@ -0,0 +1,21 @@
+/**
+ * @param {number[]} stones
+ * @return {number}
+ */
+var lastStoneWeight = function (stones) {
+  while (stones.length > 1) {
+    stones.sort((a, b) => b - a);
+    const big1 = stones.shift();
+    const big2 = stones.shift();
+
+    if (big1 !== big2) {
+      stones.push(big1 - big2);
+    }
+  }
+
+  return stones.length === 0 ? 0 : stones[0];
+};
+
+// Time taken : 7m 51s
+// Runtime : 2ms
+// Memory : 51.29MB

From 1f60059360f788604a3c00000caf03c82fb04e6a Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 29 Oct 2024 21:34:15 +0900
Subject: [PATCH 27/51] 271 / Encode and Decode Strings / Medium / 14m

---
 oh-chaeyeon/271_Encode_and_Decode_Strings.js | 33 ++++++++++++++++++++
 1 file changed, 33 insertions(+)
 create mode 100644 oh-chaeyeon/271_Encode_and_Decode_Strings.js

diff --git a/oh-chaeyeon/271_Encode_and_Decode_Strings.js b/oh-chaeyeon/271_Encode_and_Decode_Strings.js
new file mode 100644
index 0000000..39a43f1
--- /dev/null
+++ b/oh-chaeyeon/271_Encode_and_Decode_Strings.js
@@ -0,0 +1,33 @@
+class Solution {
+  /**
+   * @param {string[]} strs
+   * @returns {string}
+   */
+  encode(strs) {
+    let encodedStr = "";
+    for (const str of strs) {
+      encodedStr += str.length + "#" + str;
+    }
+    return encodedStr;
+  }
+
+  /**
+   * @param {string} str
+   * @returns {string[]}
+   */
+  decode(str) {
+    const decodedList = [];
+    let i = 0;
+
+    while (i < str.length) {
+      let j = i;
+      while (str[j] !== "#") j++;
+      const len = parseInt(str.slice(i, j));
+      decodedList.push(str.slice(j + 1, j + 1 + len));
+      i = j + 1 + len;
+    }
+    return decodedList;
+  }
+}
+
+// Time taken : 14m

From 9de1b77dd7229aa018a226a46fbc2f26db6876a5 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 29 Oct 2024 21:35:25 +0900
Subject: [PATCH 28/51] 198 / House Robber / Medium / 26m 36s

---
 oh-chaeyeon/198_House_Robber.js | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)
 create mode 100644 oh-chaeyeon/198_House_Robber.js

diff --git a/oh-chaeyeon/198_House_Robber.js b/oh-chaeyeon/198_House_Robber.js
new file mode 100644
index 0000000..909e363
--- /dev/null
+++ b/oh-chaeyeon/198_House_Robber.js
@@ -0,0 +1,23 @@
+/**
+ * @param {number[]} nums
+ * @return {number}
+ */
+var rob = function (nums) {
+  if (nums.length === 0) return 0;
+  if (nums.length === 1) return nums[0];
+
+  let prev2 = 0;
+  let prev1 = nums[0];
+
+  for (let i = 1; i < nums.length; i++) {
+    let current = Math.max(prev1, nums[i] + prev2);
+    prev2 = prev1;
+    prev1 = current;
+  }
+
+  return prev1;
+};
+
+// Time taken : 26m 36s
+// Runtime : 0ms
+// Memory : 49.07MB

From f031a31fc7a916c1ffde2e6cd1e52b7d5a7286ab Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 29 Oct 2024 21:35:57 +0900
Subject: [PATCH 29/51] 66 / Plus One / Easy / 9m 28s

---
 oh-chaeyeon/66_Plus_One.js | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)
 create mode 100644 oh-chaeyeon/66_Plus_One.js

diff --git a/oh-chaeyeon/66_Plus_One.js b/oh-chaeyeon/66_Plus_One.js
new file mode 100644
index 0000000..acd91db
--- /dev/null
+++ b/oh-chaeyeon/66_Plus_One.js
@@ -0,0 +1,20 @@
+/**
+ * @param {number[]} digits
+ * @return {number[]}
+ */
+var plusOne = function (digits) {
+  for (let i = digits.length - 1; i >= 0; i--) {
+    if (digits[i] < 9) {
+      digits[i] += 1;
+      return digits;
+    }
+
+    digits[i] = 0;
+  }
+
+  return [1, ...digits];
+};
+
+// Time taken : 9m 28s
+// Runtime : 0ms
+// Memory : 48.85MB

From 38a2fe1078e998ca3ea54fbfe55545c3452f44fa Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 29 Oct 2024 21:36:37 +0900
Subject: [PATCH 30/51] 703 / Kth Largest Element in a Stream / Easy / 40m 51s

---
 .../703_Kth_Largest_Element_in_a_Stream.js    | 39 +++++++++++++++++++
 1 file changed, 39 insertions(+)
 create mode 100644 oh-chaeyeon/703_Kth_Largest_Element_in_a_Stream.js

diff --git a/oh-chaeyeon/703_Kth_Largest_Element_in_a_Stream.js b/oh-chaeyeon/703_Kth_Largest_Element_in_a_Stream.js
new file mode 100644
index 0000000..4b510cb
--- /dev/null
+++ b/oh-chaeyeon/703_Kth_Largest_Element_in_a_Stream.js
@@ -0,0 +1,39 @@
+/**
+ * @param {number} k
+ * @param {number[]} nums
+ */
+var KthLargest = function (k, nums) {
+  this.k = k;
+  this.minHeap = new MinPriorityQueue();
+
+  for (let num of nums) {
+    this.minHeap.enqueue(num);
+    if (this.minHeap.size() > k) {
+      this.minHeap.dequeue();
+    }
+  }
+};
+
+/**
+ * @param {number} val
+ * @return {number}
+ */
+KthLargest.prototype.add = function (val) {
+  if (this.minHeap.size() < this.k || val > this.minHeap.front().element) {
+    this.minHeap.enqueue(val);
+    if (this.minHeap.size() > this.k) {
+      this.minHeap.dequeue();
+    }
+  }
+  return this.minHeap.front().element;
+};
+
+/**
+ * Your KthLargest object will be instantiated and called as such:
+ * var obj = new KthLargest(k, nums)
+ * var param_1 = obj.add(val)
+ */
+
+// Time taken : 40m 51s
+// Runtime : 51ms
+// Memory : 64.8MB

From 5210093a549f43c914c4670cea5c9456f270d3ba Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 29 Oct 2024 21:37:08 +0900
Subject: [PATCH 31/51] 704 / Binary Search / Easy / 9m 26s

---
 oh-chaeyeon/704_Binary_Search.js | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)
 create mode 100644 oh-chaeyeon/704_Binary_Search.js

diff --git a/oh-chaeyeon/704_Binary_Search.js b/oh-chaeyeon/704_Binary_Search.js
new file mode 100644
index 0000000..26bd6ff
--- /dev/null
+++ b/oh-chaeyeon/704_Binary_Search.js
@@ -0,0 +1,27 @@
+/**
+ * @param {number[]} nums
+ * @param {number} target
+ * @return {number}
+ */
+var search = function (nums, target) {
+  let left = 0;
+  let right = nums.length - 1;
+
+  while (left <= right) {
+    let mid = Math.floor(left + (right - left) / 2);
+
+    if (nums[mid] === target) {
+      return mid;
+    } else if (nums[mid] < target) {
+      left = mid + 1;
+    } else {
+      right = mid - 1;
+    }
+  }
+
+  return -1;
+};
+
+// Time taken : 9m 26s
+// Runtime : 0ms
+// Memory : 53.13MB

From 59e79d83b50e4bb1047ffbfca5b4b7f534c6d7c3 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 5 Nov 2024 21:46:45 +0900
Subject: [PATCH 32/51] 136 / Single Number / Easy / 4m 52s

---
 oh-chaeyeon/136_Single_Number.js | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)
 create mode 100644 oh-chaeyeon/136_Single_Number.js

diff --git a/oh-chaeyeon/136_Single_Number.js b/oh-chaeyeon/136_Single_Number.js
new file mode 100644
index 0000000..f8b0389
--- /dev/null
+++ b/oh-chaeyeon/136_Single_Number.js
@@ -0,0 +1,17 @@
+/**
+ * @param {number[]} nums
+ * @return {number}
+ */
+var singleNumber = function (nums) {
+  let result = 0;
+
+  for (let num of nums) {
+    result ^= num;
+  }
+
+  return result;
+};
+
+// Time taken : 4m 52s
+// Runtime : 3ms
+// Memory : 54.06MB

From df48108d849672c64eb72af705caf92b0c37e757 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 5 Nov 2024 21:47:19 +0900
Subject: [PATCH 33/51] 110 / Balanced Binary Tree / Easy / 16m 44s

---
 oh-chaeyeon/110_Balanced_Binary_Tree.js | 35 +++++++++++++++++++++++++
 1 file changed, 35 insertions(+)
 create mode 100644 oh-chaeyeon/110_Balanced_Binary_Tree.js

diff --git a/oh-chaeyeon/110_Balanced_Binary_Tree.js b/oh-chaeyeon/110_Balanced_Binary_Tree.js
new file mode 100644
index 0000000..1842245
--- /dev/null
+++ b/oh-chaeyeon/110_Balanced_Binary_Tree.js
@@ -0,0 +1,35 @@
+/**
+ * Definition for a binary tree node.
+ * function TreeNode(val, left, right) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.left = (left===undefined ? null : left)
+ *     this.right = (right===undefined ? null : right)
+ * }
+ */
+/**
+ * @param {TreeNode} root
+ * @return {boolean}
+ */
+var isBalanced = function (root) {
+  const checkHeight = (node) => {
+    if (!node) return 0;
+
+    const leftHeight = checkHeight(node.left);
+    if (leftHeight === -1) return -1;
+
+    const rightHeight = checkHeight(node.right);
+    if (rightHeight === -1) return -1;
+
+    if (Math.abs(leftHeight - rightHeight) > 1) {
+      return -1;
+    }
+
+    return Math.max(leftHeight, rightHeight) + 1;
+  };
+
+  return checkHeight(root) !== -1;
+};
+
+// Time taken : 16m 44s
+// Runtime : 1ms
+// Memory : 53.60MB

From bf2bb0e0a46ca3dcd976268fcc59a7cea9eaf4e2 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 5 Nov 2024 21:47:55 +0900
Subject: [PATCH 34/51] 54 / Spiral Matrix / Medium / 53m 19s

---
 oh-chaeyeon/54_Spiral_Matrix.js | 46 +++++++++++++++++++++++++++++++++
 1 file changed, 46 insertions(+)
 create mode 100644 oh-chaeyeon/54_Spiral_Matrix.js

diff --git a/oh-chaeyeon/54_Spiral_Matrix.js b/oh-chaeyeon/54_Spiral_Matrix.js
new file mode 100644
index 0000000..cc03e92
--- /dev/null
+++ b/oh-chaeyeon/54_Spiral_Matrix.js
@@ -0,0 +1,46 @@
+/**
+ * @param {number[][]} matrix
+ * @return {number[]}
+ */
+var spiralOrder = function (matrix) {
+  const result = [];
+
+  if (matrix.length === 0) return result;
+
+  let top = 0;
+  let bottom = matrix.length - 1;
+  let left = 0;
+  let right = matrix[0].length - 1;
+
+  while (top <= bottom && left <= right) {
+    for (let i = left; i <= right; i++) {
+      result.push(matrix[top][i]);
+    }
+    top++;
+
+    for (let i = top; i <= bottom; i++) {
+      result.push(matrix[i][right]);
+    }
+    right--;
+
+    if (top <= bottom) {
+      for (let i = right; i >= left; i--) {
+        result.push(matrix[bottom][i]);
+      }
+      bottom--;
+    }
+
+    if (left <= right) {
+      for (let i = bottom; i >= top; i--) {
+        result.push(matrix[i][left]);
+      }
+      left++;
+    }
+  }
+
+  return result;
+};
+
+// Time taken : 53m 19s
+// Runtime : 0ms
+// Memory : 48.79MB

From d75f703155fea51289a4fa979461537c9a1515b2 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 5 Nov 2024 21:48:40 +0900
Subject: [PATCH 35/51] 973 / K Closest points to Origin / Medium / 12m 42s

---
 oh-chaeyeon/973_K_Closest_points_to_Origin.js | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)
 create mode 100644 oh-chaeyeon/973_K_Closest_points_to_Origin.js

diff --git a/oh-chaeyeon/973_K_Closest_points_to_Origin.js b/oh-chaeyeon/973_K_Closest_points_to_Origin.js
new file mode 100644
index 0000000..8871b29
--- /dev/null
+++ b/oh-chaeyeon/973_K_Closest_points_to_Origin.js
@@ -0,0 +1,18 @@
+/**
+ * @param {number[][]} points
+ * @param {number} k
+ * @return {number[][]}
+ */
+var kClosest = function (points, k) {
+  points.sort((a, b) => {
+    const A = a[0] * a[0] + a[1] * a[1];
+    const B = b[0] * b[0] + b[1] * b[1];
+    return A - B;
+  });
+
+  return points.slice(0, k);
+};
+
+// Time taken : 12m 42s
+// Runtime : 34ms
+// Memory : 62.73MB

From eae2d4ceb2f0f3e2cb4e152af9e3d88875c61afd Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 5 Nov 2024 21:49:17 +0900
Subject: [PATCH 36/51] 155 / Min Stack / Medium / 1h 2m 56s

---
 oh-chaeyeon/155_Min_Stack.js | 55 ++++++++++++++++++++++++++++++++++++
 1 file changed, 55 insertions(+)
 create mode 100644 oh-chaeyeon/155_Min_Stack.js

diff --git a/oh-chaeyeon/155_Min_Stack.js b/oh-chaeyeon/155_Min_Stack.js
new file mode 100644
index 0000000..425af76
--- /dev/null
+++ b/oh-chaeyeon/155_Min_Stack.js
@@ -0,0 +1,55 @@
+var MinStack = function () {
+  this.stack = [];
+  this.minStack = [];
+};
+
+/**
+ * @param {number} val
+ * @return {void}
+ */
+MinStack.prototype.push = function (val) {
+  this.stack.push(val);
+  if (
+    this.minStack.length === 0 ||
+    val <= this.minStack[this.minStack.length - 1]
+  ) {
+    this.minStack.push(val);
+  }
+};
+
+/**
+ * @return {void}
+ */
+MinStack.prototype.pop = function () {
+  const val = this.stack.pop();
+  if (val === this.minStack[this.minStack.length - 1]) {
+    this.minStack.pop();
+  }
+};
+
+/**
+ * @return {number}
+ */
+MinStack.prototype.top = function () {
+  return this.stack[this.stack.length - 1];
+};
+
+/**
+ * @return {number}
+ */
+MinStack.prototype.getMin = function () {
+  return this.minStack[this.minStack.length - 1];
+};
+
+/**
+ * Your MinStack object will be instantiated and called as such:
+ * var obj = new MinStack()
+ * obj.push(val)
+ * obj.pop()
+ * var param_3 = obj.top()
+ * var param_4 = obj.getMin()
+ */
+
+// Time taken : 1h 2m 56s
+// Runtime : 5ms
+// Memory : 59.62MB

From d1ae91938fd3a06c8a9e24b20f66cf35d26dba72 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Wed, 13 Nov 2024 00:13:02 +0900
Subject: [PATCH 37/51] 128 / Longest consecutive sequence / Medium / 31m 17s

---
 .../128_Longest_consecutive_sequence.js       | 25 +++++++++++++++++++
 1 file changed, 25 insertions(+)
 create mode 100644 oh-chaeyeon/128_Longest_consecutive_sequence.js

diff --git a/oh-chaeyeon/128_Longest_consecutive_sequence.js b/oh-chaeyeon/128_Longest_consecutive_sequence.js
new file mode 100644
index 0000000..89d1eba
--- /dev/null
+++ b/oh-chaeyeon/128_Longest_consecutive_sequence.js
@@ -0,0 +1,25 @@
+/**
+ * @param {number[]} nums
+ * @return {number}
+ */
+var longestConsecutive = function (nums) {
+  const numSet = new Set(nums);
+  let max = 0;
+
+  for (let num of numSet) {
+    if (!numSet.has(num - 1)) {
+      let length = 1;
+
+      while (numSet.has(num + length)) {
+        length += 1;
+      }
+
+      max = Math.max(max, length);
+    }
+  }
+  return max;
+};
+
+// Time taken : 31m 17s
+// Runtime : 35ms
+// Memory : 72.97MB

From db6e78416de663f4e9680c72a4285314b6e707fa Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Wed, 13 Nov 2024 00:13:32 +0900
Subject: [PATCH 38/51] 371 / Sum of two Integers / Medium / 15m 48s

---
 oh-chaeyeon/371_Sum_of_two_Integers.js | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)
 create mode 100644 oh-chaeyeon/371_Sum_of_two_Integers.js

diff --git a/oh-chaeyeon/371_Sum_of_two_Integers.js b/oh-chaeyeon/371_Sum_of_two_Integers.js
new file mode 100644
index 0000000..5703597
--- /dev/null
+++ b/oh-chaeyeon/371_Sum_of_two_Integers.js
@@ -0,0 +1,22 @@
+/**
+ * @param {number} a
+ * @param {number} b
+ * @return {number}
+ */
+var getSum = function (a, b) {
+  if (a === 0) return b;
+  if (b === 0) return a;
+
+  while (b != 0) {
+    let sum = a ^ b;
+    let carry = (a & b) << 1;
+
+    a = sum;
+    b = carry;
+  }
+  return a;
+};
+
+// Time taken : 15m 48s
+// Runtime : 0ms
+// Memory : 49.15MB

From efe5ca20fbf9020767975d58e1f9e1dfe675b44d Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Wed, 13 Nov 2024 00:13:59 +0900
Subject: [PATCH 39/51] 208 / Implement Trie Prefix Tree / Medium / 57m 29s

---
 oh-chaeyeon/208_Implement_Trie_Prefix_Tree.js | 60 +++++++++++++++++++
 1 file changed, 60 insertions(+)
 create mode 100644 oh-chaeyeon/208_Implement_Trie_Prefix_Tree.js

diff --git a/oh-chaeyeon/208_Implement_Trie_Prefix_Tree.js b/oh-chaeyeon/208_Implement_Trie_Prefix_Tree.js
new file mode 100644
index 0000000..9dd97ec
--- /dev/null
+++ b/oh-chaeyeon/208_Implement_Trie_Prefix_Tree.js
@@ -0,0 +1,60 @@
+var Trie = function () {
+  this.root = {};
+};
+
+/**
+ * @param {string} word
+ * @return {void}
+ */
+Trie.prototype.insert = function (word) {
+  let node = this.root;
+  for (let char of word) {
+    if (!node[char]) {
+      node[char] = {};
+    }
+    node = node[char];
+  }
+  node.isEnd = true;
+};
+
+/**
+ * @param {string} word
+ * @return {boolean}
+ */
+Trie.prototype.search = function (word) {
+  let node = this.root;
+  for (let char of word) {
+    if (!node[char]) {
+      return false;
+    }
+    node = node[char];
+  }
+  return node.isEnd === true;
+};
+
+/**
+ * @param {string} prefix
+ * @return {boolean}
+ */
+Trie.prototype.startsWith = function (prefix) {
+  let node = this.root;
+  for (let char of prefix) {
+    if (!node[char]) {
+      return false;
+    }
+    node = node[char];
+  }
+  return true;
+};
+
+/**
+ * Your Trie object will be instantiated and called as such:
+ * var obj = new Trie()
+ * obj.insert(word)
+ * var param_2 = obj.search(word)
+ * var param_3 = obj.startsWith(prefix)
+ */
+
+// Time taken : 57m 29s
+// Runtime : 50ms
+// Memory : 64.72MB

From cd94c0294584b1c559621ee0a6a946c6a9720217 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Wed, 13 Nov 2024 00:14:22 +0900
Subject: [PATCH 40/51] 226 / Invert Binary Tree / Easy / 30m 34s

---
 oh-chaeyeon/226_Invert_Binary_Tree.js | 30 +++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)
 create mode 100644 oh-chaeyeon/226_Invert_Binary_Tree.js

diff --git a/oh-chaeyeon/226_Invert_Binary_Tree.js b/oh-chaeyeon/226_Invert_Binary_Tree.js
new file mode 100644
index 0000000..2dc04ea
--- /dev/null
+++ b/oh-chaeyeon/226_Invert_Binary_Tree.js
@@ -0,0 +1,30 @@
+/**
+ * Definition for a binary tree node.
+ * function TreeNode(val, left, right) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.left = (left===undefined ? null : left)
+ *     this.right = (right===undefined ? null : right)
+ * }
+ */
+/**
+ * @param {TreeNode} root
+ * @return {TreeNode}
+ */
+var invertTree = function (root) {
+  if (root === null) {
+    return null;
+  }
+
+  let temp = root.left;
+  root.left = root.right;
+  root.right = temp;
+
+  invertTree(root.left);
+  invertTree(root.right);
+
+  return root;
+};
+
+// Time taken : 30m 34s
+// Runtime : 0ms
+// Memory : 49.28MB

From bff831052f94942d65b01fa338fb6196fc5d5abe Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Wed, 13 Nov 2024 00:14:45 +0900
Subject: [PATCH 41/51] 543 / Diameter of Binary Tree / Easy / 31m 55s

---
 oh-chaeyeon/543_Diameter_of_Binary_Tree.js | 33 ++++++++++++++++++++++
 1 file changed, 33 insertions(+)
 create mode 100644 oh-chaeyeon/543_Diameter_of_Binary_Tree.js

diff --git a/oh-chaeyeon/543_Diameter_of_Binary_Tree.js b/oh-chaeyeon/543_Diameter_of_Binary_Tree.js
new file mode 100644
index 0000000..8aca5b3
--- /dev/null
+++ b/oh-chaeyeon/543_Diameter_of_Binary_Tree.js
@@ -0,0 +1,33 @@
+/**
+ * Definition for a binary tree node.
+ * function TreeNode(val, left, right) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.left = (left===undefined ? null : left)
+ *     this.right = (right===undefined ? null : right)
+ * }
+ */
+/**
+ * @param {TreeNode} root
+ * @return {number}
+ */
+var diameterOfBinaryTree = function (root) {
+  let diameter = 0;
+
+  const Tree = (node) => {
+    if (!node) return 0;
+
+    let leftHeight = Tree(node.left);
+    let rightHeight = Tree(node.right);
+
+    diameter = Math.max(diameter, leftHeight + rightHeight);
+
+    return Math.max(leftHeight, rightHeight) + 1;
+  };
+
+  Tree(root);
+  return diameter;
+};
+
+// Time taken : 31m 55s
+// Runtime : 2ms
+// Memory : 55.43MB

From 5f23ce0cd986706f99c73816c292dd40d11630fc Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 19 Nov 2024 21:13:04 +0900
Subject: [PATCH 42/51] 201 / Binary Tree Level Order Traversal / Medium / 21m
 49s

---
 .../201_Binary_Tree_Level_Order_Traversal.js  | 33 +++++++++++++++++++
 1 file changed, 33 insertions(+)
 create mode 100644 oh-chaeyeon/201_Binary_Tree_Level_Order_Traversal.js

diff --git a/oh-chaeyeon/201_Binary_Tree_Level_Order_Traversal.js b/oh-chaeyeon/201_Binary_Tree_Level_Order_Traversal.js
new file mode 100644
index 0000000..7cf6b41
--- /dev/null
+++ b/oh-chaeyeon/201_Binary_Tree_Level_Order_Traversal.js
@@ -0,0 +1,33 @@
+/**
+ * Definition for a binary tree node.
+ * function TreeNode(val, left, right) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.left = (left===undefined ? null : left)
+ *     this.right = (right===undefined ? null : right)
+ * }
+ */
+/**
+ * @param {TreeNode} root
+ * @return {number[][]}
+ */
+var levelOrder = function (root) {
+  const result = [];
+  const Tree = (node, level) => {
+    if (!node) return;
+
+    if (result.length === level) {
+      result.push([]);
+    }
+
+    result[level].push(node.val);
+    Tree(node.left, level + 1);
+    Tree(node.right, level + 1);
+  };
+
+  Tree(root, 0);
+  return result;
+};
+
+// Time taken : 21m 49s
+// Runtime : 1ms
+// Memory : 55.59MB

From 91c0914d51910f076964d04daac935024b309240 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 19 Nov 2024 21:13:37 +0900
Subject: [PATCH 43/51] 572 / Subtree Of Another Tree / Easy / 25m 09s

---
 oh-chaeyeon/572_Subtree_Of_Another_Tree.js | 39 ++++++++++++++++++++++
 1 file changed, 39 insertions(+)
 create mode 100644 oh-chaeyeon/572_Subtree_Of_Another_Tree.js

diff --git a/oh-chaeyeon/572_Subtree_Of_Another_Tree.js b/oh-chaeyeon/572_Subtree_Of_Another_Tree.js
new file mode 100644
index 0000000..4ffffe7
--- /dev/null
+++ b/oh-chaeyeon/572_Subtree_Of_Another_Tree.js
@@ -0,0 +1,39 @@
+/**
+ * Definition for a binary tree node.
+ * function TreeNode(val, left, right) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.left = (left===undefined ? null : left)
+ *     this.right = (right===undefined ? null : right)
+ * }
+ */
+/**
+ * @param {TreeNode} root
+ * @param {TreeNode} subRoot
+ * @return {boolean}
+ */
+var isSubtree = function (root, subRoot) {
+  if (!subRoot) return true;
+  if (!root) return false;
+
+  if (root.val === subRoot.val) {
+    const checkSame = (node1, node2) => {
+      if (!node1 && !node2) return true;
+      if (!node1 || !node2) return false;
+      if (node1.val !== node2.val) return false;
+
+      return (
+        checkSame(node1.left, node2.left) && checkSame(node1.right, node2.right)
+      );
+    };
+
+    if (checkSame(root, subRoot)) {
+      return true;
+    }
+  }
+
+  return isSubtree(root.left, subRoot) || isSubtree(root.right, subRoot);
+};
+
+// Time taken : 25m 09s
+// Runtime : 6ms
+// Memory : 55.18MB

From a5d9426d5cfaaa830f80fd65d38968e331de2fc4 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 19 Nov 2024 21:14:26 +0900
Subject: [PATCH 44/51] 213 / House Robber II / Medium / 20m 31s

---
 oh-chaeyeon/213_House_Robber_II.js | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)
 create mode 100644 oh-chaeyeon/213_House_Robber_II.js

diff --git a/oh-chaeyeon/213_House_Robber_II.js b/oh-chaeyeon/213_House_Robber_II.js
new file mode 100644
index 0000000..b2e8140
--- /dev/null
+++ b/oh-chaeyeon/213_House_Robber_II.js
@@ -0,0 +1,27 @@
+/**
+ * @param {number[]} nums
+ * @return {number}
+ */
+var rob = function (nums) {
+  const n = nums.length;
+
+  if (n === 0) return 0;
+  if (n === 1) return nums[0];
+
+  const FindMoney = (houses) => {
+    let one = 0,
+      two = 0;
+    for (let money of houses) {
+      const temp = one;
+      one = Math.max(one, two + money);
+      two = temp;
+    }
+    return one;
+  };
+
+  return Math.max(FindMoney(nums.slice(0, n - 1)), FindMoney(nums.slice(1)));
+};
+
+// Time taken : 20m 31s
+// Runtime : 0ms
+// Memory : 48.34MB

From 89099b63a4ced465d7ad7e8ce02f851421ca1f10 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 19 Nov 2024 21:14:51 +0900
Subject: [PATCH 45/51] 207 / Course Schedule / Medium / 21m 49s

---
 oh-chaeyeon/207_Course_Schedule.js | 35 ++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)
 create mode 100644 oh-chaeyeon/207_Course_Schedule.js

diff --git a/oh-chaeyeon/207_Course_Schedule.js b/oh-chaeyeon/207_Course_Schedule.js
new file mode 100644
index 0000000..cfdc143
--- /dev/null
+++ b/oh-chaeyeon/207_Course_Schedule.js
@@ -0,0 +1,35 @@
+/**
+ * @param {number} numCourses
+ * @param {number[][]} prerequisites
+ * @return {boolean}
+ */
+var canFinish = function (numCourses, prerequisites) {
+  const graph = Array.from({ length: numCourses }, () => []);
+  for (const [a, b] of prerequisites) {
+    graph[b].push(a);
+  }
+
+  const visited = new Array(numCourses).fill(0);
+
+  const dfs = (course) => {
+    if (visited[course] === 1) return false;
+    if (visited[course] === 2) return true;
+
+    visited[course] = 1;
+    for (const nextCourse of graph[course]) {
+      if (!dfs(nextCourse)) return false;
+    }
+    visited[course] = 2;
+    return true;
+  };
+
+  for (let i = 0; i < numCourses; i++) {
+    if (!dfs(i)) return false;
+  }
+
+  return true;
+};
+
+// Time taken : 21m 49s
+// Runtime : 14ms
+// Memory : 55.35MB

From fccee21e4994579a4e1624a0f62b3b85da51cef0 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 19 Nov 2024 21:15:14 +0900
Subject: [PATCH 46/51] 150 / Evaluate Reverse Polish Notation / Medium / 14m
 58s

---
 .../150_Evaluate_Reverse_Polish_Notation.js   | 38 +++++++++++++++++++
 1 file changed, 38 insertions(+)
 create mode 100644 oh-chaeyeon/150_Evaluate_Reverse_Polish_Notation.js

diff --git a/oh-chaeyeon/150_Evaluate_Reverse_Polish_Notation.js b/oh-chaeyeon/150_Evaluate_Reverse_Polish_Notation.js
new file mode 100644
index 0000000..dd94b85
--- /dev/null
+++ b/oh-chaeyeon/150_Evaluate_Reverse_Polish_Notation.js
@@ -0,0 +1,38 @@
+/**
+ * @param {string[]} tokens
+ * @return {number}
+ */
+var evalRPN = function (tokens) {
+  const stack = [];
+  for (const token of tokens) {
+    if (!isNaN(token)) {
+      stack.push(Number(token));
+    } else {
+      const b = stack.pop();
+      const a = stack.pop();
+
+      let result;
+      switch (token) {
+        case "+":
+          result = a + b;
+          break;
+        case "-":
+          result = a - b;
+          break;
+        case "*":
+          result = a * b;
+          break;
+        case "/":
+          result = Math.trunc(a / b);
+          break;
+      }
+      stack.push(result);
+    }
+  }
+
+  return stack.pop();
+};
+
+// Time taken : 14m 58s
+// Runtime : 2ms
+// Memory : 51.92MB

From 2720f06ae83aa28c5b8edf834e3766dcd532daa6 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 26 Nov 2024 21:59:36 +0900
Subject: [PATCH 47/51] 56 / Merge Intervals / Medium / 23m 25s

---
 oh-chaeyeon/56_Merge_Intervals.js | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)
 create mode 100644 oh-chaeyeon/56_Merge_Intervals.js

diff --git a/oh-chaeyeon/56_Merge_Intervals.js b/oh-chaeyeon/56_Merge_Intervals.js
new file mode 100644
index 0000000..5b518dd
--- /dev/null
+++ b/oh-chaeyeon/56_Merge_Intervals.js
@@ -0,0 +1,29 @@
+/**
+ * @param {number[][]} intervals
+ * @return {number[][]}
+ */
+var merge = function (intervals) {
+  if (intervals.length === 0) return [];
+  intervals.sort((a, b) => a[0] - b[0]);
+
+  const merged = [intervals[0]];
+
+  for (let i = 1; i < intervals.length; i++) {
+    const current = intervals[i];
+
+    if (current[0] <= merged[merged.length - 1][1]) {
+      merged[merged.length - 1][1] = Math.max(
+        merged[merged.length - 1][1],
+        current[1]
+      );
+    } else {
+      merged.push(current);
+    }
+  }
+
+  return merged;
+};
+
+// Time taken : 23m 25s
+// Runtime : 7ms
+// Memory : 59.04MB

From 13fc2c3a9fec64c79020dee326db6b91fa4d3812 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 26 Nov 2024 22:00:05 +0900
Subject: [PATCH 48/51] 1584 / Min Cost to Connect all points / Medium / 1h+

---
 .../1584_Min_Cost_to_Connect_all_points.js    | 41 +++++++++++++++++++
 1 file changed, 41 insertions(+)
 create mode 100644 oh-chaeyeon/1584_Min_Cost_to_Connect_all_points.js

diff --git a/oh-chaeyeon/1584_Min_Cost_to_Connect_all_points.js b/oh-chaeyeon/1584_Min_Cost_to_Connect_all_points.js
new file mode 100644
index 0000000..7ca304b
--- /dev/null
+++ b/oh-chaeyeon/1584_Min_Cost_to_Connect_all_points.js
@@ -0,0 +1,41 @@
+/**
+ * @param {number[][]} points
+ * @return {number}
+ */
+var minCostConnectPoints = function (points) {
+  const n = points.length;
+  const dist = new Array(n).fill(Infinity);
+  const visited = new Array(n).fill(false);
+  dist[0] = 0;
+  let cost = 0;
+
+  for (let i = 0; i < n; i++) {
+    let minCost = Infinity;
+    let currentNode = -1;
+
+    for (let j = 0; j < n; j++) {
+      if (!visited[j] && dist[j] < minCost) {
+        minCost = dist[j];
+        currentNode = j;
+      }
+    }
+
+    visited[currentNode] = true;
+    cost += minCost;
+
+    for (let nextNode = 0; nextNode < n; nextNode++) {
+      if (!visited[nextNode]) {
+        const manhattanDistance =
+          Math.abs(points[currentNode][0] - points[nextNode][0]) +
+          Math.abs(points[currentNode][1] - points[nextNode][1]);
+        dist[nextNode] = Math.min(dist[nextNode], manhattanDistance);
+      }
+    }
+  }
+
+  return cost;
+};
+
+// Time taken : 1h+
+// Runtime : 33ms
+// Memory : 52.37MB

From 78f1f2cfa1cd2046ab0818f9abe8f58cad0d9b56 Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 26 Nov 2024 22:00:31 +0900
Subject: [PATCH 49/51] 235 / Lowest Common ancestor of a Binary Search Tree /
 Medium / 9m 37s

---
 ...Common_ancestor_of_a_Binary_Search_Tree.js | 30 +++++++++++++++++++
 1 file changed, 30 insertions(+)
 create mode 100644 oh-chaeyeon/235_Lowest_Common_ancestor_of_a_Binary_Search_Tree.js

diff --git a/oh-chaeyeon/235_Lowest_Common_ancestor_of_a_Binary_Search_Tree.js b/oh-chaeyeon/235_Lowest_Common_ancestor_of_a_Binary_Search_Tree.js
new file mode 100644
index 0000000..32182d3
--- /dev/null
+++ b/oh-chaeyeon/235_Lowest_Common_ancestor_of_a_Binary_Search_Tree.js
@@ -0,0 +1,30 @@
+/**
+ * Definition for a binary tree node.
+ * function TreeNode(val) {
+ *     this.val = val;
+ *     this.left = this.right = null;
+ * }
+ */
+
+/**
+ * @param {TreeNode} root
+ * @param {TreeNode} p
+ * @param {TreeNode} q
+ * @return {TreeNode}
+ */
+var lowestCommonAncestor = function (root, p, q) {
+  while (root) {
+    if (p.val < root.val && q.val < root.val) {
+      root = root.left;
+    } else if (p.val > root.val && q.val > root.val) {
+      root = root.right;
+    } else {
+      return root;
+    }
+  }
+  return null;
+};
+
+// Time taken : 9m 37s
+// Runtime : 56ms
+// Memory : 58.70MB

From 812d16f4afb262425c9448bee403b136823043ed Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 26 Nov 2024 22:01:02 +0900
Subject: [PATCH 50/51] 139 / Word Break / Medium / 12m 49s

---
 oh-chaeyeon/139_Word_Break.js | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)
 create mode 100644 oh-chaeyeon/139_Word_Break.js

diff --git a/oh-chaeyeon/139_Word_Break.js b/oh-chaeyeon/139_Word_Break.js
new file mode 100644
index 0000000..022de5f
--- /dev/null
+++ b/oh-chaeyeon/139_Word_Break.js
@@ -0,0 +1,30 @@
+/**
+ * @param {string} s
+ * @param {string[]} wordDict
+ * @return {boolean}
+ */
+var wordBreak = function (s, wordDict) {
+  const wordSet = new Set(wordDict);
+  const dp = new Array(s.length + 1).fill(false);
+  dp[0] = true;
+
+  for (let i = 1; i <= s.length; i++) {
+    for (const word of wordSet) {
+      const wordLength = word.length;
+      if (
+        i >= wordLength &&
+        dp[i - wordLength] &&
+        s.substring(i - wordLength, i) === word
+      ) {
+        dp[i] = true;
+        break;
+      }
+    }
+  }
+
+  return dp[s.length];
+};
+
+// Time taken : 12m 49s
+// Runtime : 3ms
+// Memory : 51.24MB

From 622454d73e5112526be12e84470650d80be87c5b Mon Sep 17 00:00:00 2001
From: oh-chaeyeon <chaebread555@gmail.com>
Date: Tue, 26 Nov 2024 22:01:33 +0900
Subject: [PATCH 51/51] 215 / Kth largest element in an Array / Medium / 30m+

---
 .../215_Kth largest_element_in_an_Array.js    | 46 +++++++++++++++++++
 1 file changed, 46 insertions(+)
 create mode 100644 oh-chaeyeon/215_Kth largest_element_in_an_Array.js

diff --git a/oh-chaeyeon/215_Kth largest_element_in_an_Array.js b/oh-chaeyeon/215_Kth largest_element_in_an_Array.js
new file mode 100644
index 0000000..01dc25a
--- /dev/null
+++ b/oh-chaeyeon/215_Kth largest_element_in_an_Array.js	
@@ -0,0 +1,46 @@
+/**
+ * @param {number[]} nums
+ * @param {number} k
+ * @return {number}
+ */
+var findKthLargest = function (nums, k) {
+  const maxHeap = new MaxPriorityQueue();
+
+  for (const num of nums) {
+    maxHeap.enqueue(num);
+  }
+
+  for (let i = 0; i < k - 1; i++) {
+    maxHeap.dequeue();
+  }
+  return maxHeap.front().element;
+};
+
+// Time taken : 16m 50s
+// Runtime : 148ms
+// Memory : 77.60MB
+
+//----------------------------------------------------
+
+/**
+ * @param {number[]} nums
+ * @param {number} k
+ * @return {number}
+ */
+var findKthLargest = function (nums, k) {
+  const offset = 10000;
+  const count = new Array(20001).fill(0);
+
+  for (let num of nums) {
+    count[num + offset]++;
+  }
+
+  let total = 0;
+  for (let i = count.length - 1; i >= 0; i--) {
+    total += count[i];
+    if (total >= k) return i - offset;
+  }
+};
+
+// Runtime : 5ms
+// Memory : 58.40MB