JSFiddle - React, Tailwind, and code Playground

by Nic Fontaine

JavaScript

var singleNumber = function(nums) {
    let obj = {}
    for (let n of nums) {
        if (n in obj) { delete obj[n] }
        else { obj[n] = 1 }
    }
    return Object.keys[obj]
};

console.log(singleNumber([1, 2, 2]))