JSFiddle - React, Tailwind, and code Playground

by asdf

JavaScript

// Find first non-repeating character in a string, for example:
// ‘abaacbbkc’ -> ‘k'
// ‘abcd’ -> ‘a’
// ‘aabccd’ -> ‘b’ (symbol ‘d’ is also non-repeating, but it is not first non-repeating character)

fuction firstUniqueChar(str) {
debugger;
	var map = {};
  for (var i=0; i<str.length; i++) {
  	if (!map[str[i]]) {
    	map[str[i]] = 0;
    } 
  	map[str[i]] += 1; 
  }
  for (var prop in map) {
  	if (map[prop] === 1) {
    	return prop;
    } else {
    	return null;
    }
  }
}
console.log(firstUniqueChar('abaacbbkc'));
console.log(firstUniqueChar('abcd'));
console.log(firstUniqueChar('aabccd'));