[printjin-gmailcom] Week 4 Solutions

word-search/printjin-gmailcom.py

@@ -0,0 +1,23 @@
+from typing import List
+
+class Solution:
+    def exist(self, board, word):
+        m, n = len(board), len(board[0])
+        def dfs(x, y, index):
+            if index == len(word):
+                return True
+            if x < 0 or x >= m or y < 0 or y >= n or board[x][y] != word[index]:
+                return False
+            temp = board[x][y]
+            board[x][y] = '#'
+            found = (
+                dfs(x + 1, y, index + 1) or dfs(x - 1, y, index + 1) or dfs(x, y + 1, index + 1) or dfs(x, y - 1, index + 1)
+                )
+            board[x][y] = temp
+            return found
+
+        for i in range(m):
+            for j in range(n):
+                if dfs(i, j, 0):
+                    return True
+        return False