0567.Permutation-in-String

Author: kimi0230

Leetcode/0567.Permutation-in-String/README.md

@@ -0,0 +1,125 @@
+# [567. Permutation in String](https://leetcode.com/problems/permutation-in-string/)
+###### tags: `Medium` `Leetcode` `Sliding Window`
+
+## 題目
+Given two strings s1 and s2, return true if s2 contains a permutation of s1, or false otherwise.
+
+In other words, return true if one of s1's permutations is the substring of s2.
+
+
+Example 1:
+```
+Input: s1 = "ab", s2 = "eidbaooo"
+Output: true
+Explanation: s2 contains one permutation of s1 ("ba").
+```
+
+Example 2:
+
+Input: s1 = "ab", s2 = "eidboaoo"
+Output: false
+ 
+
+Constraints:
+
+* 1 <= s1.length, s2.length <= 104
+* s1 and s2 consist of lowercase English letters.
+
+## 題目大意
+輸入兩個String S1 和 S2 , 判斷 S2 是否包含S1的排列, 也就是要判斷 S2 中是否存在一個子字串是S1的一種全排列
+
+## 解題思路
+Sliding Window
+可以用 slice 取代 map 來優化
+
+## 來源
+* https://leetcode.com/problems/permutation-in-string/
+
+## 解答
+https://github.com/kimi0230/LeetcodeGolang/blob/master/Leetcode/0567.Permutation-in-String/main.go
+
+```go
+package permutationinstring
+
+func CheckInclusion(s1 string, s2 string) bool {
+	need, window := make(map[rune]int), make(map[rune]int)
+	for _, c := range s1 {
+		need[c]++
+	}
+
+	left, right := 0, 0
+	valid := 0
+	for right < len(s2) {
+		c := rune(s2[right])
+		right++
+
+		// 進行窗口內數據的一系列更新
+		if need[c] > 0 {
+			window[c]++
+			if window[c] == need[c] {
+				// 該字符長度達到
+				valid++
+			}
+		}
+
+		// fmt.Printf("[%d,%d) \n", left, right)
+
+		// 判斷左視窗是否要收縮
+		// for (right - left) >= len(s1)
+		if (right - left) >= len(s1) {
+
+			if valid == len(need) {
+				// 全找到
+				return true
+			}
+			d := rune(s2[left])
+			left++
+			if need[d] > 0 {
+				if window[d] == need[d] {
+					valid--
+				}
+				window[d]--
+			}
+		}
+	}
+	return false
+}
+
+// 用 slice 取代 map 來優化
+func CheckInclusionSlice(s1 string, s2 string) bool {
+	need := [256]int{}
+	for _, c := range s1 {
+		need[c-'a']++
+	}
+
+	left, right := 0, 0
+	count := len(s1)
+	for right < len(s2) {
+		c := s2[right] - 'a'
+
+		if need[c] > 0 {
+			// 有找到
+			count--
+		}
+		need[c]--
+		right++
+
+		// fmt.Printf("[%d,%d)\n", left, right)
+		if count == 0 {
+			return true
+		}
+
+		// 判斷左視窗是否要收縮
+		if (right - left) == len(s1) {
+			d := s2[left] - 'a'
+			if need[d] >= 0 {
+				// 符合預期的長度, 但是卻沒找到預期的結果
+				count++
+			}
+			need[d]++
+			left++
+		}
+	}
+	return false
+}
+```

Leetcode/0567.Permutation-in-String/main.go

@@ -0,0 +1,83 @@
+package permutationinstring
+
+func CheckInclusion(s1 string, s2 string) bool {
+	need, window := make(map[rune]int), make(map[rune]int)
+	for _, c := range s1 {
+		need[c]++
+	}
+
+	left, right := 0, 0
+	valid := 0
+	for right < len(s2) {
+		c := rune(s2[right])
+		right++
+
+		// 進行窗口內數據的一系列更新
+		if need[c] > 0 {
+			window[c]++
+			if window[c] == need[c] {
+				// 該字符長度達到
+				valid++
+			}
+		}
+
+		// fmt.Printf("[%d,%d) \n", left, right)
+
+		// 判斷左視窗是否要收縮
+		// for (right - left) >= len(s1)
+		if (right - left) >= len(s1) {
+
+			if valid == len(need) {
+				// 全找到
+				return true
+			}
+			d := rune(s2[left])
+			left++
+			if need[d] > 0 {
+				if window[d] == need[d] {
+					valid--
+				}
+				window[d]--
+			}
+		}
+	}
+	return false
+}
+
+// 用 slice 取代 map 來優化
+func CheckInclusionSlice(s1 string, s2 string) bool {
+	need := [256]int{}
+	for _, c := range s1 {
+		need[c-'a']++
+	}
+
+	left, right := 0, 0
+	count := len(s1)
+	for right < len(s2) {
+		c := s2[right] - 'a'
+
+		if need[c] > 0 {
+			// 有找到
+			count--
+		}
+		need[c]--
+		right++
+
+		// fmt.Printf("[%d,%d)\n", left, right)
+		if count == 0 {
+			return true
+		}
+
+		// 判斷左視窗是否要收縮
+		if (right - left) == len(s1) {
+			d := s2[left] - 'a'
+			if need[d] >= 0 {
+				// 符合預期的長度, 但是卻沒找到預期的結果
+				count++
+			}
+			need[d]++
+			left++
+		}
+	}
+	return false
+}

Leetcode/0567.Permutation-in-String/main_test.go

@@ -0,0 +1,62 @@
+package permutationinstring
+
+import "testing"
+
+var tests = []struct {
+	arg1 string
+	arg2 string
+	want bool
+}{
+	{
+		"ab",
+		"eidbaooo",
+		true,
+	},
+	{
+		"ab",
+		"eidboaoo",
+		false,
+	},
+}
+
+func TestCheckInclusion(t *testing.T) {
+	for _, tt := range tests {
+		if got := CheckInclusion(tt.arg1, tt.arg2); got != tt.want {
+			t.Errorf("got = %v, want = %v", got, tt.want)
+		}
+	}
+}
+
+func TestCheckInclusionSlice(t *testing.T) {
+	for _, tt := range tests {
+		if got := CheckInclusionSlice(tt.arg1, tt.arg2); got != tt.want {
+			t.Errorf("got = %v, want = %v", got, tt.want)
+		}
+	}
+}
+
+func BenchmarkCheckInclusion(b *testing.B) {
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		CheckInclusion(tests[0].arg1, tests[0].arg2)
+	}
+}
+
+func BenchmarkCheckInclusionSlice(b *testing.B) {
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		CheckInclusionSlice(tests[0].arg1, tests[0].arg2)
+	}
+}
+
+/*
+go test -benchmem -run=none LeetcodeGolang/Leetcode/0567.Permutation-in-String -bench=.
+goos: darwin
+goarch: amd64
+pkg: LeetcodeGolang/Leetcode/0567.Permutation-in-String
+cpu: Intel(R) Core(TM) i5-8259U CPU @ 2.30GHz
+BenchmarkCheckInclusion-8                9091321               167.9 ns/op             0 B/op          0 allocs/op
+BenchmarkCheckInclusionSlice-8          26744336                53.28 ns/op            0 B/op          0 allocs/op
+PASS
+ok      LeetcodeGolang/Leetcode/0567.Permutation-in-String      3.143s
+*/

README.md

@@ -133,6 +133,7 @@ void slidingWindow(string s, string t){
     int left = 0 , right = 0
     int valid = 0
 
+    // 先移動 right 再移動 left. 直到right到達 string的末端
     while(right < s.size()){
         // c是將移入窗口的字符
         char c = s[right]
@@ -159,6 +160,7 @@ void slidingWindow(string s, string t){
 | No. | Title | Solution | Difficulty | Time | Space | Topic |
 |-----|:-----:|:--------:|------------|------|-------|-------|
 | 0209 | [Minimum Size Subarray Sum](https://leetcode.com/problems/minimum-size-subarray-sum/) | [Go](https://github.com/kimi0230/LeetcodeGolang/tree/master/Leetcode/0209.Minimum-Size-Subarray-Sum) | Medium | O(n^2) / O(n) / O(nlog n) |  O(1) / O(1) / O(n) | Sliding Window |
+| 0567 | [Permutation in String](https://leetcode.com/problems/permutation-in-string/) | [Go](https://github.com/kimi0230/LeetcodeGolang/tree/master/Leetcode/0567.Permutation-in-String) | Medium | O(n) |  O(1) | Sliding Window |
 
 ---