comefrom: <awangdev>1048. Longest String Chain_2.java
code: private List[] buildBucket(String[] words) {
  
          List[] bucket = new List[17];
          for (String w : words) {
              int len = w.length();
              if (bucket[len] == null) bucket[len] = new ArrayList<>();
              bucket[len].add(w);
          }
          return bucket;
      }
masked: private List [ ] var_0 ( String [ ] var_1 ) {
    List [ ] var_2 = new List [ 17 ] ;
    for ( String var_3 : var_1 ) {
      int var_4 = var_3 . length ( ) ;
      if ( var_2 [ var_4 ] == null ) var_2 [ var_4 ] = new ArrayList < > ( ) ;
      var_2 [ var_4 ] . add ( var_3 ) ;
    }
    return var_2 ;
  }
  