public  String plusOut(String str, String word) {
    String res = "";
    for(int i = 0; i < str.length() - word.length() + 1; i++) {
      if(str.substring(i, i+word.length()).equals(word)) {
        res += word ;
        i += word.length() - 1;
      }
      else { res += "+"; }
    }
    int i = res.length();
    while(i < str.length()) {
      res += "+";
      i++;
    }
    return res;
  }