JSFiddle - React, Tailwind, and code Playground

by brigand

JavaScript

const digits = '0123456789ABCDEF';
let num = '1299';

function incr(n) {
  let parts = n.split('');
  for (let i = parts.length - 1; i >= -1; i -= 1) {
    const digitIndex = digits.indexOf(n[i]);
    if (i === -1) {
      parts.unshift('1')
    } else if (digits[digitIndex + 1]) {
      parts[i] = digits[digitIndex + 1]
      break
    } else {
      parts[i] = 0;
    }

  }
  return parts.join('');
}


console.log(incr(num))