Get closest value of a number from array

Question

I have an array:

["7", "8", "11", "13", "14"]

I want the closest inferior number to 11 if any (i.e., 8), or if such a number does not exist, then the closest superior number to 11 (i.e., 13).

Answer 1

Try the below shortest method for getting the closest value:

n = 40
a = [20, 30, 45, 50, 56, 60, 64, 80]
a.min_by{|x| (n-x).abs}