Remove duplicate characters from string

Question

I have to make a function in JavaScript that removes all duplicated letters in a string. So far I\'ve been able to do this: If I have the word \"anaconda\" it shows me as a

Answer 1

Just wanted to add my solution for fun:

function removeDoubles(string) {
  var mapping = {};
  var newString = '';

  for (var i = 0; i < string.length; i++) {
    if (!(string[i] in mapping)) {
      newString += string[i];
      mapping[string[i]] = true;
    }
  }
  return newString;
}