Merge Two Sorted Array

You are given two sorted arrays, A and B, and A has a large enough
buffer at the end to hold B  Write a method to merge B into A in sorted
order
Paint Fill

Implement the “paint fill” function that one might see on many image
editing programs That is, given a screen (represented by a 2 dimensional
array of Colors), a point, and a new color, fill in the surrounding area
until you hit a border of that color’
Hanoi tower