Convert letters to reversed alphabet

by SHELDON PASCIAK

JavaScript

const AtoZ = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
const reversedLowercase = 'zyxwvutsrqponmlkjihgfedcba';

// Encode A-Z → reversed lowercase
function caesarEncode(str) {
  return str.toUpperCase().split('').map(char => {
    const index = AtoZ.indexOf(char);
    return index !== -1 ? reversedLowercase[index] : char;
  }).join('');
}

// Decode reversed lowercase → A-Z
function caesarDecode(str) {
  return str.split('').map(char => {
    const index = reversedLowercase.indexOf(char);
    return index !== -1 ? AtoZ[index] : char;
  }).join('');
}

let a = caesarEncode("SHELDON");

let b = caesarDecode(a);

console.log(a,b);