Given a sorted array and a number k, find the pair in an array whose sum is equal to k

https://gist.github.com/evgenii-malov/b57760739894ca64691677213cf6c32a

Find predecessor and successor for a given element in a sorted list with Haskell - https://youtube.com/video/oCiR3Rk7H_Y ... https://www.youtube.com/watch?v=JPikTujq6mw