Algorithms in Javascript: CTCI 1.1 - Is Unique: Write a function to determine if a string has all unique characters.

ctci-1.1-string-has-all-unique-characters-2.js

const stringHasUniqueChars = (str) => {
  let count = {};
  for(let i=0; i<str.length; i++) {
    count[str[i]] = count[str[i]] === undefined ? 1: count[str[i]]+1;
    if(count[str[i]] > 1) 
      return false;
  }
  return true;
}

const s = 'Geeks for Geeks';
const y = stringHasUniqueChars(s);
const x = 'abc';
const z = stringHasUniqueChars(x);
console.log(s + ': ' + y);
console.log(x + ': ' + z);