085 Maximal Rectangle

这道题主要是使用084的方法， 唯一要做的是处理一下输入 ，具体代码如下 复杂度O(n*n)

 1 class Solution:
 2     # @param {character[][]} matrix
 3     # @return {integer}
 4     def maximalRectangle(self, matrix):
 5         ans = 0
 6         for i in range(0,len(matrix)):
 7             for j in range(0, len(matrix[0])):
 8                 if i == 0:
 9                     matrix[i][j] = int(matrix[i][j])
10                 else:
11                     if matrix[i][j] == "0":
12                         matrix[i][j] = 0
13                     else:
14                         matrix[i][j] = matrix[i-1][j] + 1
15         for m in matrix:
16             ans = max(ans, self.largestRectangleArea(m))
17         return ans
18 
19     def largestRectangleArea(self, height):
20         ans = 0
21         s = []
22         for i in range(0, len(height)):
23             left = i
24             while (s != []) and (s[-1][0] > height[i]):
25                 left = s[-1][1]
26                 ans = max(ans, (i - left) * s[-1][0])
27                 s.pop()
28             s.append([height[i], left])
29         right = len(height)
30         while s != []:
31             left = s[-1][1]
32             ans = max(ans, (right - left) * s[-1][0])
33             s.pop()
34         return ans

 

posted @ 2015-07-06 07:49  dapanshe  阅读(120)  评论(0)  编辑  收藏  举报