day3

main2.dart

void main() {
  print(isIsogram2('qw- - e rty'));
  print(isIsogram('qw- - e rty'));
}

String letters = 'abcdefghijklmnopqrstuvwxyz';


bool isIsogram(String word){
  String newStr = '';
  for(int i = 0; i < word.length; i++){
    var letter = word[i];
    if(newStr.contains(letter) && letters.contains(letter)){
      return false;
    }else{
      newStr += letter;
    }
  }
  return true;
}

bool isIsogram2(word){
  for(int i = 0; i < word.length; i++){
    var letter = word[i];
    if(word.indexOf(letter) != word.lastIndexOf(letter) && letters.contains(letter)){
      return false;
    }
  }
  return true;
}