comefrom: <gouthampradhan>string_KeyboardRow_1.java
code: public String[] findWords(String[] words) {
      String R1 = "qwertyuiop";
      String R2 = "asdfghjkl";
      String R3 = "zxcvbnm";
      List<String> answer = new ArrayList<>();
      for (String s : words) {
        Set<Character> set = new HashSet<>();
        for (char c : s.toCharArray()) {
          if (R1.indexOf(c) != -1) {
            set.add('1');
          } else if (R2.indexOf(c) != -1) {
            set.add('2');
          } else if (R3.indexOf(c) != -1) {
            set.add('3');
          }
        }
        if (set.size() == 1) {
          answer.add(s);
        }
      }
      String[] ans = new String[answer.size()];
      int i = 0;
      for (String s : answer) {
        ans[i++] = s;
      }
      return ans;
    }
masked: public String [ ] var_0 ( String [ ] var_2 ) {
    String var_4 = "qwertyuiop" ;
    String var_6 = "asdfghjkl" ;
    String var_8 = "zxcvbnm" ;
    List < String > var_11 = new ArrayList < > ( ) ;
    for ( String var_12 : var_2 ) {
      Set < Character > var_16 = new HashSet < > ( ) ;
      for ( char var_18 : var_12 . toCharArray ( ) ) {
        if ( var_4 . indexOf ( var_18 ) != - 1 ) {
          var_16 . add ( '1' ) ;
        }
        else if ( var_6 . indexOf ( var_18 ) != - 1 ) {
          var_16 . add ( '2' ) ;
        }
        else if ( var_8 . indexOf ( var_18 ) != - 1 ) {
          var_16 . add ( '3' ) ;
        }
      }
      if ( var_16 . size ( ) == 1 ) {
        var_11 . add ( var_12 ) ;
      }
    }
    String [ ] var_26 = new String [ var_11 . size ( ) ] ;
    int var_28 = 0 ;
    for ( String var_12 : var_11 ) {
      var_26 [ var_28 ++ ] = var_12 ;
    }
    return var_26 ;
  }
  