solve longest repeating character replacement

Author: SamTheKorean

longest-repeating-character-replacement/samthekorean.py

@@ -0,0 +1,20 @@
+# TC : O(n)
+# SC : O(1)
+class Solution:
+    def characterReplacement(self, s: str, k: int) -> int:
+        count = {}
+        result = 0
+
+        left = 0
+        maxFrequency = 0
+        for right in range(len(s)):
+            count[s[right]] = 1 + count.get(s[right], 0)
+            maxFrequency = max(maxFrequency, count[s[right]])
+
+            while (right - left + 1) - maxFrequency > k:
+                count[s[left]] -= 1
+                left += 1
+
+            result = max(result, right - left + 1)
+
+        return result