PLease answer

A bakery sells donuts in boxes of two different quantities, X and 22. Additionally, each box requires work wi, wa to assemble. You are given an integer n and must return the minimum work set of boxes to get exactly n donuts, if n is possible; or o if it is impossible. For example if x1 = 6, C2 = 9, wj = 1, W2 = 3 and n = 18, then you should return: 3 boxes of size x1 = 6, for total work of 3. However, if n = 11, you should return 0. A coworker suggests the following greedy algorithm for this problem. Always use the box requiring minimum work. Give an example with li, W; and n values, showing this greedy algorithm fails