comefrom: <awangdev>Unique Binary Search Tree_1.java
code: public int numTrees(int n) {
          if ( n <= 1) {
              return 1;
          }
          final int[] numTree = new int[n + 1];
          numTree[0] = 1;
          for (int i = 1; i <= n; i++) {
              for (int j = 0; j < i; j++) {
                  numTree[i] += numTree[j] * numTree[i - j - 1];
              }
          }
          return numTree[n];
      }
masked: public int sample_funcname ( int var_0 ) {
    if ( var_0 <= 1 ) {
      return 1 ;
    }
    final int [ ] var_1 = new int [ var_0 + 1 ] ;
    var_1 [ 0 ] = 1 ;
    for ( int var_2 = 1 ;
    var_2 <= var_0 ;
    var_2 ++ ) {
      for ( int var_3 = 0 ;
      var_3 < var_2 ;
      var_3 ++ ) {
        var_1 [ var_2 ] += var_1 [ var_3 ] * var_1 [ var_2 - var_3 - 1 ] ;
      }
    }
    return var_1 [ var_0 ] ;
  }
  