Find the number in an array that is closest to a given number

Question

I have an Array of integers in javascript, [5,10,15,20,25,30,35] when given a number x, how can I find the element in the array that is closest to that number?

Answer 1

Assuming the array is sorted, step through each adjacent pair of integers in the array. For each pair (say "5 and 10" or "20 and 25"), test if x is in between them, and if so, return whichever one is closer to x (with a bias towards the lower one).

You would also need a special case for when x is less than the first number (return the first number) or greater than the last number (return the last number).

If the array is not sorted, sort it first.