Why am I still getting "false" even after entering right number?

Question

Can you find out what's wrong here? Why am I still getting "false" even after entering right number? here is my code..

var rand = Math.floor(Math.random() * 10);
var guess = window.prompt('guess the number!');
if (rand === guess)
  console.log('correct');
else
  console.log('false');
console.log(`correct number is : ${rand}`);

Does this answer your question? [Javascript if statements don't work](https://stackoverflow.com/questions/31240549/javascript-if-statements-dont-work) — Sebastian Simon, Apr 05 '21 at 07:24

Emiel Zuurbier · Answer 1 · 2021-04-05T07:25:18.097

It's because you use the strict equality operator === which also takes data types into consideration. The rand value is a number, but the guess value is a string. Therefor the two can never be equal even if the represented value is the same.

var rand = Math.floor(Math.random() * 10);
var guess = window.prompt('guess the number!');

console.log(typeof rand);
console.log(typeof guess);

You could solve this by using the equality operator..

var rand = Math.floor(Math.random() * 10);
var guess = window.prompt('guess the number!');

if (rand == guess)
  console.log('correct');
else
  console.log('false');
console.log(`correct number is : ${rand}`);

..changing the rand number to a string..

var rand = Math.floor(Math.random() * 10);
var guess = window.prompt('guess the number!');

if (rand.toString() === guess)
  console.log('correct');
else
  console.log('false');
console.log(`correct number is : ${rand}`);

..or by changing the guess string to a number

var rand = Math.floor(Math.random() * 10);
var guess = window.prompt('guess the number!');

if (rand === parseInt(guess, 10))
  console.log('correct');
else
  console.log('false');
console.log(`correct number is : ${rand}`);

Why am I still getting "false" even after entering right number?

1 Answers1