1277. Count Square Submatrices with All Ones.java

class Solution {
    public int countSquares(int[][] matrix) {
    int dp[][] = new int[matrix.length+1][matrix[0].length+1];
    int ans = 0; 
    for(int i=0; i<matrix.length; i++)
    {
      for(int j=0; j<matrix[0].length; j++)
      {
        if(matrix[i][j]==1)
        dp[i+1][j+1] = 1 + Math.min(dp[i][j], Math.min(dp[i+1][j], dp[i][j+1]));
        ans += dp[i+1][j+1];
      }  
    }  
    return ans;  
    }
}