% store_credit.pi
% https://code.google.com/codejam/contest/351101/dashboard#s=p0
% Qualification Round Africa 2010
% Problem A. Store Credit
%
% to use: picat store_credit < input_file > output_file
%
main =>
    T = read_int(),
    foreach (TC in 1..T)
        C = read_int(),
        N = read_int(),
        Items = {read_int() : _ in 1..N},
        Map = new_map(),
        foreach (I in N..-1..1)
            Is = Map.get(Items[I], []),
            Map.put(Items[I],[I|Is])
        end,
        do_case(TC, C, Items, Map)
    end.

do_case(TC, C, Items, Map),
   between(1, len(Items)-1, I),
   Js = Map.get(C-Items[I], []),
   member(J, Js),
   I < J
=>
   printf("Case #%w: %w %w\n", TC, I, J).

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