comefrom: <awangdev>Interleaving String_1.java
code: public boolean isInterleave(String s1, String s2, String s3) {
          if (s1 == null || s2 == null || s1.length() + s2.length() != s3.length()) {
              return false;
          }
          int m = s1.length();
          int n = s2.length();
          boolean[][] dp = new boolean[m + 1][n + 1];
          
          for (int i = 0; i <= m; i++) {
              for (int j = 0; j <= n; j++) {
                  if (i == 0 && j == 0) { 
                      dp[i][j] = true;
                      continue;
                  }
                  
                  dp[i][j] = false;
                  if (i > 0 && s1.charAt(i - 1) == s3.charAt(i + j - 1)) {
                      dp[i][j] |= dp[i - 1][j];
                  } 
                  
                  if (j > 0 && s2.charAt(j - 1) == s3.charAt(i + j - 1)) {
                      dp[i][j] |= dp[i][j - 1];
                  }
              }
          }
          return dp[m][n];
      }
masked: public boolean var_0 ( String var_1 , String var_2 , String var_3 ) {
    if ( var_1 == null || var_2 == null || var_1 . length ( ) + var_2 . length ( ) != var_3 . length ( ) ) {
      return false ;
    }
    int var_4 = var_1 . length ( ) ;
    int var_5 = var_2 . length ( ) ;
    boolean [ ] [ ] var_6 = new boolean [ var_4 + 1 ] [ var_5 + 1 ] ;
    for ( int var_7 = 0 ;
    var_7 <= var_4 ;
    var_7 ++ ) {
      for ( int var_8 = 0 ;
      var_8 <= var_5 ;
      var_8 ++ ) {
        if ( var_7 == 0 && var_8 == 0 ) {
          var_6 [ var_7 ] [ var_8 ] = true ;
          continue ;
        }
        var_6 [ var_7 ] [ var_8 ] = false ;
        if ( var_7 > 0 && var_1 . charAt ( var_7 - 1 ) == var_3 . charAt ( var_7 + var_8 - 1 ) ) {
          var_6 [ var_7 ] [ var_8 ] |= var_6 [ var_7 - 1 ] [ var_8 ] ;
        }
        if ( var_8 > 0 && var_2 . charAt ( var_8 - 1 ) == var_3 . charAt ( var_7 + var_8 - 1 ) ) {
          var_6 [ var_7 ] [ var_8 ] |= var_6 [ var_7 ] [ var_8 - 1 ] ;
        }
      }
    }
    return var_6 [ var_4 ] [ var_5 ] ;
  }
  