"Countdown" numbers game solver

This solver tries all combinations and prints solutions that are only at least as good as the best solution it has found so far.

"Countdown" is normally played with exactly six numbers, chosen from 1 - 10, 25, 50, 75, and 100; but actually you can feed in all sorts of numbers here, and you don't have to have six of them. 

Numbers:            

Target: