Google - First char once

by Anton Bagayev

JavaScript

var findFirstCharOnce = function (inputStr) {
	let counts = {};
	for (let i = 0; i < inputStr.length; i++){
		let charAtI = inputStr[i];
		if (counts[charAtI] == undefined){
			counts[charAtI] = 1;
		} else {
			counts[charAtI]++;
		}
	}
	let uniqueChars = Object.keys(counts);
	let result = "none";
	for (let i = 0; i < uniqueChars.length; i++){
		if (counts[uniqueChars[i]] == 1){
			result = uniqueChars[i];
			break;
		}
	}
	return result;
}

console.log(findFirstCharOnce("abaccdeff"));