comefrom: <qiyuangong>819_Most_Common_Word_1.java
code: public String mostCommonWord(String paragraph, String[] banned) {
          paragraph += ".";
  
          Set<String> banset = new HashSet();
          for (String word: banned) banset.add(word);
          Map<String, Integer> count = new HashMap();
  
          String ans = "";
          int ansfreq = 0;
  
          StringBuilder word = new StringBuilder();
          for (char c: paragraph.toCharArray()) {
              if (Character.isLetter(c)) {
                  word.append(Character.toLowerCase(c));
              } else if (word.length() > 0) {
                  String finalword = word.toString();
                  if (!banset.contains(finalword)) {
                      count.put(finalword, count.getOrDefault(finalword, 0) + 1);
                      if (count.get(finalword) > ansfreq) {
                          ans = finalword;
                          ansfreq = count.get(finalword);
                      }
                  }
                  word = new StringBuilder();
              }
          }
          return ans;
      }
masked: public String var_0 ( String var_1 , String [ ] var_2 ) {
    var_1 += "." ;
    Set < String > var_3 = new HashSet ( ) ;
    for ( String var_4 : var_2 ) var_3 . add ( var_4 ) ;
    Map < String , Integer > var_5 = new HashMap ( ) ;
    String var_6 = "" ;
    int var_7 = 0 ;
    StringBuilder var_4 = new StringBuilder ( ) ;
    for ( char var_8 : var_1 . toCharArray ( ) ) {
      if ( Character . isLetter ( var_8 ) ) {
        var_4 . append ( Character . toLowerCase ( var_8 ) ) ;
      }
      else if ( var_4 . length ( ) > 0 ) {
        String var_9 = var_4 . toString ( ) ;
        if ( ! var_3 . contains ( var_9 ) ) {
          var_5 . put ( var_9 , var_5 . getOrDefault ( var_9 , 0 ) + 1 ) ;
          if ( var_5 . get ( var_9 ) > var_7 ) {
            var_6 = var_9 ;
            var_7 = var_5 . get ( var_9 ) ;
          }
        }
        var_4 = new StringBuilder ( ) ;
      }
    }
    return var_6 ;
  }
  