finished solution for problem64

Author: dampdigits

problem64/Solution.py

@@ -0,0 +1,21 @@
+class Solution:
+    def longestCommonSubsequence(self, text1: str, text2: str) -> int:
+        n, m = len(text1), len(text2)
+        cache = [[0] * m for _ in range(n)]
+        has_cache = [[False] * m for _ in range(n)]
+
+        def findLCS(i, j):
+            if i == n or j == m: return 0
+            if has_cache[i][j]: return cache[i][j]
+
+            if text1[i] != text2[j]:
+                cache[i][j] = max(
+                    findLCS(i+1, j),
+                    findLCS(i, j+1)
+                )
+            else: cache[i][j] = findLCS(i+1, j+1) +1
+            
+            has_cache[i][j] = True
+            return cache[i][j]
+
+        return findLCS(0,0)