Leetcode 算法设计 第十三周

221. Maximal Square

Given a 2D binary matrix filled with 0’s and 1’s, find the largest square containing only 1’s and return its area.
For example, given the following matrix:
1 0 1 0 0
1 0 1 1 1
1 1 1 1 1
1 0 0 1 0
Return 4.

题目大意

在给定的数组中找到元素都为1的最大矩阵

我的解答

class Solution {public:    int maximalSquare(vector<vector<char>>& matrix) {        if(matrix.size() == 0)return 0;        int maxsqu = 0;        int x = matrix.size();        int y = matrix[0].size();        vector<vector<int>> dp(x+1,vector<int>(y+1,0));        for(int i = 1; i <= x; i++){            for(int j = 1; j <= y; j++){                if(matrix[i-1][j-1] == '1'){                    dp[i][j] = min(min(dp[i-1][j-1],dp[i-1][j]),dp[i][j-1])+1;                    maxsqu = max(maxsqu,dp[i][j]);                }            }        }        return maxsqu * maxsqu;    }};