comefrom: <awangdev>221. Maximal Square_1.java
code: public int maximalSquare(char[][] matrix) {
          if (matrix == null || matrix.length == 0 || matrix[0] == null || matrix[0].length == 0) return 0;
          int m = matrix.length, n = matrix[0].length;
          int[][] dp = new int[m + 1][n + 1];
          int maxLen = 0;
         
          for (int i = 1; i <= m; i++) {
              for (int j = 1; j <= n; j++) {
                  if (matrix[i - 1][j - 1] == '0') continue;
                  dp[i][j] = Math.min(Math.min(dp[i][j-1], dp[i-1][j]), dp[i-1][j-1]) + 1;
                  maxLen = Math.max(maxLen, dp[i][j]);
              }
          }
          return maxLen * maxLen;
      }
masked: public int sample_funcname ( char [ ] [ ] var_0 ) {
    if ( var_0 == null || var_0 . length == 0 || var_0 [ 0 ] == null || var_0 [ 0 ] . length == 0 ) return 0 ;
    int var_1 = var_0 . length , var_2 = var_0 [ 0 ] . length ;
    int [ ] [ ] var_3 = new int [ var_1 + 1 ] [ var_2 + 1 ] ;
    int var_4 = 0 ;
    for ( int var_5 = 1 ;
    var_5 <= var_1 ;
    var_5 ++ ) {
      for ( int var_6 = 1 ;
      var_6 <= var_2 ;
      var_6 ++ ) {
        if ( var_0 [ var_5 - 1 ] [ var_6 - 1 ] == '0' ) continue ;
        var_3 [ var_5 ] [ var_6 ] = Math . min ( Math . min ( var_3 [ var_5 ] [ var_6 - 1 ] , var_3 [ var_5 - 1 ] [ var_6 ] ) , var_3 [ var_5 - 1 ] [ var_6 - 1 ] ) + 1 ;
        var_4 = Math . max ( var_4 , var_3 [ var_5 ] [ var_6 ] ) ;
      }
    }
    return var_4 * var_4 ;
  }
  