I'm working on a random number guessing game in JavaScript. I want the user to input a lowLimit and a highLimit and have the random number generated between those two numbers. I tried hardcoding the lowLimit and highLimit as below:
let lowLimit = 5;
let highLimit = 20;
let random = Math.floor(Math.random() * highLimit);
if (random < lowLimit) {
random += lowLimit;
}
console.log(random);
and everything works well.
However, when I allow the user to input values, the random number always becomes the sum of lowLimit and upperLimit. I cannot figure this out!
My final code is this:
let lowLimit = prompt('Input the lower limit:');
let highLimit = prompt('Input the upper limit:');
let random = Math.floor(Math.random() * highLimit);
let tries = 0;
if (random < lowLimit) {
random += lowLimit;
}
console.log(random);
let guess = prompt('Secret number generated. Enter guess:');
while (guess !== random) {
if (guess === 'q') break;
tries += 1;
if (guess > random) {
prompt('You guessed too high. Guess again...');
} else if (guess < random) {
prompt('You guessed too low. Guess again...');
} else {
alert('You guessed correctly! You made ' + tries + " guesses.");
}
}
This solution works. Any refactoring suggestions are welcome.
let lowLimit = Number(prompt('Input the lower limit:'));
let highLimit = Number(prompt('Input the upper limit:'));
while (!lowLimit || !highLimit) {
lowLimit = Number(prompt('Input a valid lower limit:'));
highLimit = Number(prompt('Input a valid upper limit:'));
}
lowLimit = Number(lowLimit);
highLimit = Number(highLimit);
let random = Math.floor(Math.random() * (highLimit - lowLimit) + lowLimit);
let guesses = 0;
console.log(random);
guess = prompt('Enter guess:');
while (guess !== random) {
if (guess === 'q') {
alert('Ok. Quitting... You made ' + guesses + ' guesses')
break;
}
guesses += 1;
guess = Number(guess);
if (guess > random) {
guess = prompt('You guessed too high. Guess again...');
} else if (guess < random) {
guess = prompt('You guessed too low. Guess again...');
} else alert('You guessed correctly! You made ' + guesses + " guesses.");
}
A few tweaks to improve the code, and one bug fix (the case where user guesses correctly on the first try, they will receive no feedback)...
// + is concise way to coerce an int
const lowLimit = +prompt('Input the lower limit:');
const highLimit = +prompt('Input the upper limit:');
// note - we could add checks here for invalid or disordered values
// this presumes we want random to be exclusive of highLimit. if not, we'll need to tweak
const random = Math.floor(Math.random() * (highLimit - lowLimit) + lowLimit);
// we'll vary the prompt during the game
let promptMsg = 'Enter guess:', guesses = 0, guess;
// bug fix and cleanup: do while, so we always play at least once
// prompt in just one place, alter the prompt message to represent game state
do {
guess = prompt(promptMsg);
guesses++;
if (guess !== 'q') {
guess = +guess;
if (guess > random) {
promptMsg = 'You guessed too high. Guess again...';
} else if (guess < random) {
promptMsg = 'You guessed too low. Guess again...';
}
}
} while (guess !== 'q' && guess !== random);
const endMsg = guess === 'q' ? 'Ok. Quitting' : 'You guessed correctly.'
const guessesMsg = `You made ${guesses} ${guesses === 1 ? 'guess' : 'guesses'}`;
alert(`${endMsg} ${guessesMsg}`)We can generate a random number by using the Date.now()
let res = Date.now() % (highLimit - lowLimit + 1) + lowLimit.
This is because nobody can estimate the time in milisecond the code runs.