% 2017 Round 1C, Problem C, in Picat, by Afa Zhou
% https://code.google.com/codejam/contest/3274486/dashboard#s=p2&a=2
% Core Training
% for Small dataset

import util.

main() =>
    T = readln().to_int(),
    foreach(TC in 1..T)
        [_N,_K] = [X.to_number() : X in readln().split()],
        U = readln().to_number(),
        P = [X.to_number() : X in readln().split()].sort(),
        dc(TC,U,1,P)
    end.

dc(TC,U,Count,[P1]) =>
    Delta = U/Count,
    printf(stderr,"Case #%d: %f\n",TC,(P1+Delta)**Count).
dc(TC,U,Count,[P1,P2|P]) =>
    D = P2-P1,
    (Count*D < U ->
        dc(TC,U-Count*D,Count+1,[P2|P])
    ;
        Delta = U/Count,
        printf(stderr,"Case #%d: %f\n",TC,(P1+Delta)**Count*prod([P2|P]))
    ).
    

    

picat-lang.org