In the United Kingdom the currency is made up of pound (£) and pence (p).
There are eight coins in general circulation:
1p, 2p, 5p, 10p, 20p, 50p, £1 (100p), and £2 (200p).
It is possible to make £2 in the following way:
1×£1 + 1×50p + 2×20p + 1×5p + 1×2p + 3×1p
How many different ways can £2 be made using any number of coins?
This one about broke my head. The real insight was how to count through the
different combinations of coins, but the real struggle was how to make an algorithm
that would do it.
Basically, I checked if adding one more coin would be more than my limit, if so,
I reset it to 0 and incremented the next coin. It was a bit more convoluted
than that but that's the gist of it.
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