Minesweeper

Author: lessfish

Algorithms/Minesweeper/minesweeper.py

@@ -0,0 +1,46 @@
+# Source : https://leetcode.com/problems/minesweeper/?tab=Description
+# Author : Han Zichi
+# Date   : 2017-03-07
+
+class Solution(object):
+    def updateBoard(self, board, click):
+        """
+        :type board: List[List[str]]
+        :type click: List[int]
+        :rtype: List[List[str]]
+        """
+        n, m = len(board), len(board[0])
+        dir = [[1, 0], [-1, 0], [0, 1], [0, -1], [-1, -1], [-1, 1], [1, -1], [1, 1]]
+
+        def isNotInMap(x, y):
+            return x < 0 or x >= n or y < 0 or y >= m
+
+        def getMineNum(x, y):
+            num = 0
+            for i in range(8):
+                _x, _y = x + dir[i][0], y + dir[i][1]
+                if isNotInMap(_x, _y):
+                    continue
+                if board[_x][_y] == 'M':
+                    num += 1
+            if num == 0:
+                return 'B'
+            else:
+                return str(num)
+
+        def dfs(x, y):
+            if board[x][y] == 'M':
+                board[x][y] = 'X'
+            else:
+                board[x][y] = getMineNum(x, y)
+                if board[x][y] == 'B':
+                    for i in range(8):
+                        _x, _y = x + dir[i][0], y + dir[i][1]
+                        if isNotInMap(_x, _y):
+                            continue
+                        if board[_x][_y] != 'E': # not an empty cell
+                            continue
+                        dfs(_x, _y)
+
+        dfs(click[0], click[1])
+        return board