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russelldb/Change from a dollar.erl

Created October 10, 2009 22:19
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Change from a dollar.erl
-module(change).
-compile(export_all).
count_change(Amount, CoinSet) ->
FList = lists:sort(CoinSet),
Fd = fun(X) ->
lists:nth(X, FList) end,
cc(Amount, length(CoinSet), Fd).
cc(0, _C, _Fd) -> 1;
cc(N, C, _Fd) when N < 0 ; C =:= 0-> 0;
cc(Amount, Coins, Fd) ->
cc(Amount, Coins-1, Fd) + cc(Amount - Fd(Coins), Coins, Fd).
%% Thanks http://mitpress.mit.edu/sicp/full-text/book/book-Z-H-11.html#%_sec_1.2.2
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