JSFiddle - React, Tailwind, and code Playground

by Roman Zharikov

HTML

<input type="text" id="num" placeholder="num">
<button>Узнать</button>
<h1>Результат</h1>

CSS

h1 {
  padding: 10px;
  border: 1px solid #ccc;
  text-align: center;
}

JavaScript

// hexlet course  =>   Введение в программирование
// author         =>   Roman Zharikov (zharikov.site)

//document.addEventListener("DOMContentLoaded", function() {

// define function
const smallestDivisor = (num) => {
  let divisor = 2;
  if (num === 1) {
    return 1;
  } else if (num === 0 || num < 0) {
    return NaN;
  } else {
    if (num % divisor === 0)
      return divisor;
    else
      while (num % divisor !== 0)
        divisor++;
    return divisor
  }
}

var button = document.getElementsByTagName('button')[0],
  out = document.getElementsByTagName('h1')[0],
  input = document.getElementById('num');

button.addEventListener('click', function() {

  // call function and out result to DOM element
  out.innerHTML = smallestDivisor(parseInt(input.value));

});

//});