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diff --git a/Problem1.py b/Problem1.py
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+"""
+We check if the difference between the number and the index is not 1, then we return the shift the right pointer and left pointer accordingly to the condition
+the SC for this is O(1) ad tc is o(logn) due to binary search
+"""
+
+
+# #find missing integer in array of 1 to n
+
+def solution(arr):
+    left = 0
+    right = len(arr) - 1
+
+    while right - left > 1:
+        mid = left + (right - left) // 2
+        if arr[left] - left != arr[mid] - mid:
+            right = mid
+        else: 
+            left = mid
+    return arr[left] + 1 #since answer is gauranteed to be there
+
+arr = [1, 2, 3, 5, 6, 7]
+print(solution(arr))
+