Leetcode 1493 answer

Author: Kondareddy1209

Leetcode/Leetcode_1493.py

@@ -0,0 +1,79 @@
+"""
+Problem: Longest Subarray of 1's After Deleting One Element
+
+Approach: Sliding Window
+
+We maintain a window that contains at most ONE zero.
+Why? Because we are allowed to delete one element.
+
+So if the window has:
+- 0 zeros → all 1's → we must delete one → length = window_size - 1
+- 1 zero → delete that zero → remaining all 1's
+
+Hence, answer = r - l
+"""
+
+class Solution:
+    # ----------------------------------------
+    # VERSION 1: Using WHILE loop
+    # ----------------------------------------
+    def longestSubarray_while(self, nums):
+        l = 0
+        r = 0
+        count_0 = 0  # count of zeros in window
+        ans = 0
+
+        while r < len(nums):
+            # Step 1: Expand window
+            if nums[r] == 0:
+                count_0 += 1
+
+            # Step 2: Shrink window if more than 1 zero
+            while count_0 > 1:
+                if nums[l] == 0:
+                    count_0 -= 1
+                l += 1
+
+            # Step 3: Update answer
+            # r - l instead of (r - l + 1) because we must delete one element
+            ans = max(ans, r - l)
+
+            r += 1
+
+        return ans
+
+    # ----------------------------------------
+    # VERSION 2: Using FOR loop (Recommended)
+    # ----------------------------------------
+    def longestSubarray_for(self, nums):
+        l = 0
+        count_0 = 0
+        ans = 0
+
+        for r in range(len(nums)):
+            # Step 1: Expand window
+            if nums[r] == 0:
+                count_0 += 1
+
+            # Step 2: Shrink window if more than 1 zero
+            while count_0 > 1:
+                if nums[l] == 0:
+                    count_0 -= 1
+                l += 1
+
+            # Step 3: Update answer
+            ans = max(ans, r - l)
+
+        return ans
+
+
+# ----------------------------------------
+# 🔍 Example Usage (for testing locally)
+# ----------------------------------------
+if __name__ == "__main__":
+    sol = Solution()
+
+    nums = [1, 1, 0, 1]
+
+    print("While Loop Version:", sol.longestSubarray_while(nums))
+    print("For Loop Version:", sol.longestSubarray_for(nums))