freeCodeCamp/curriculum/challenges/en/02-javascript-algorithms-and-data-structures/basic-javascript/generate-random-whole-numbers-within-a-range.en.md

id, title, challengeType

id	title	challengeType
cf1111c1c12feddfaeb2bdef	Generate Random Whole Numbers within a Range	1

Description

Instead of generating a random number between zero and a given number like we did before, we can generate a random number that falls within a range of two specific numbers. To do this, we'll define a minimum number min and a maximum number max. Here's the formula we'll use. Take a moment to read it and try to understand what this code is doing: Math.floor(Math.random() * (max - min + 1)) + min

Instructions

Create a function called randomRange that takes a range myMin and myMax and returns a random number that's greater than or equal to myMin, and is less than or equal to myMax, inclusive.

Tests

- text: 'The lowest random number that can be generated by <code>randomRange</code> should be equal to your minimum number, <code>myMin</code>.'
  testString: 'assert(calcMin === 5, ''The lowest random number that can be generated by <code>randomRange</code> should be equal to your minimum number, <code>myMin</code>.'');'
- text: 'The highest random number that can be generated by <code>randomRange</code> should be equal to your maximum number, <code>myMax</code>.'
  testString: 'assert(calcMax === 15, ''The highest random number that can be generated by <code>randomRange</code> should be equal to your maximum number, <code>myMax</code>.'');'
- text: 'The random number generated by <code>randomRange</code> should be an integer, not a decimal.'
  testString: 'assert(randomRange(0,1) % 1 === 0 , ''The random number generated by <code>randomRange</code> should be an integer, not a decimal.'');'
- text: '<code>randomRange</code> should use both <code>myMax</code> and <code>myMin</code>, and return a random number in your range.'
  testString: 'assert((function(){if(code.match(/myMax/g).length > 1 && code.match(/myMin/g).length > 2 && code.match(/Math.floor/g) && code.match(/Math.random/g)){return true;}else{return false;}})(), ''<code>randomRange</code> should use both <code>myMax</code> and <code>myMin</code>, and return a random number in your range.'');'

Challenge Seed

// Example
function ourRandomRange(ourMin, ourMax) {

  return Math.floor(Math.random() * (ourMax - ourMin + 1)) + ourMin;
}

ourRandomRange(1, 9);

// Only change code below this line.

function randomRange(myMin, myMax) {

  return 0; // Change this line

}

// Change these values to test your function
var myRandom = randomRange(5, 15);

After Test

console.info('after the test');

Solution

function randomRange(myMin, myMax) {
  return Math.floor(Math.random() * (myMax - myMin + 1)) + myMin;
}