Leetcode problem 48 - Smallest Even Multiple

Given a positive integer n, return the smallest positive integer that is a multiple of both 2 and n.

Example 1:

Input: n = 5 Output: 10 Explanation: The smallest multiple of both 5 and 2 is 10. Example 2:

Input: n = 6 Output: 6 Explanation: The smallest multiple of both 6 and 2 is 6. Note that a number is a multiple of itself.

Constraints:

1 <= n <= 150

/**
 * @param {number} n
 * @return {number}
 */
var smallestEvenMultiple = function(n) {
    if(n % 2 === 0){
        return n
    }
    return n * 2
};

Imagine you have a number, like 3 or 4, and you want to find the smallest number that you can make by using only this number and doubling it. If you already have a number like 4, which is even (because you can divide it by 2 with no leftover), you don’t need to do anything because 4 is the smallest even number you can make. But if you have a number like 3, which is not even (because you can’t divide it by 2 with nothing left), you can make the smallest even number by doubling it, which would be 6.