Online Node.js Compiler

const str = 'abcdef'; const reverseSorting = (str = '') => { const strArr = str.split(''); const mapString = 'abcdefghijkmnopqrstuvwxyz'; const sorter = (a, b) => { return mapString.indexOf(b) - mapString.indexOf(a); }; strArr.sort(sorter); return strArr.join(''); }; console.log(reverseSorting(str));