Untitled

class Solution{
public:
    int solve(vector<vector<int>> &mat,int i,int j,int &maxi, vector<vector<int>>&dp){
        if( i>= mat.size()  || j>= mat[0].size()){
            return 0;
        }
        
        if(dp[i][j]!=-1) return dp[i][j];
        
        int right=solve(mat,i,j+1,maxi,dp);
        int down=solve(mat,i+1,j,maxi,dp);
        int diag=solve(mat,i+1,j+1,maxi,dp);
        
        if(mat[i][j]==1){
            dp[i][j]=1+min(right,min(diag,down));
            maxi=max(maxi,dp[i][j]);
            return dp[i][j];
            
        }else{
            return dp[i][j]=0;
        }

    }

    int maxSquare(int n, int m, vector<vector<int>> mat){
        int maxi=0;
        vector<vector<int>> dp(n, vector<int> (m,-1));
        solve(mat,0,0,maxi,dp);
        return maxi;
    } 
};