JSFiddle - React, Tailwind, and code Playground

by Fareez Ahmed

JavaScript

function commonCharacters(str1, str2) {
    var common = str1.split('').concat(str2.split(''))
    // console.log(common);
    var hash = {};
    var out = [];

    for (var i = 0; i < common.length; i++) {
        var letter = common[i];
        if (!hash[letter]) {
            hash[letter] = 1;
        } else {
            hash[letter]++;
        }
    }
    for (var key in hash) {
        if (hash[key] > 1) {
            out.push(key);
        }
    }
    return out.join('');
}
console.log(commonCharacters('acexivou', 'aegihobu'));