Maximal square

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

Java Solution

`

public int maximalSquare(char[][] matrix) {
   int rows = matrix.length;
    if(rows==0){
        return 0;
    }        
    
    int column = matrix[0].length;
    
    int[][] dp = new int[rows+1][column+1];
    
    
    int largest = 0;
    
    for(int i=1; i<=rows; i++){
        for(int j=1; j<=column; j++){
            
            if(matrix[i-1][j-1] == '1'){
                dp[i][j] = 1+ Math.min(dp[i-1][j-1], Math.min(dp[i-1][j],dp[i][j-1]));
                
                largest = Math.max(largest, dp[i][j]);
            }
            
        }
    }
    
    return largest*largest; 
}

`