% welcome.pi  (in Picat)
% Declaratively solving Google Code Jam problems with Picat, PADL'15
% Sergii Dymchenko and Mariia Mykhailova
% http://goo.gl/qeLls4 
% Qualification Round 2009
% Problem C. Welcome to Code Jam
%
% to use: picat welcome < input_file > output_file
%

main =>
    T = read_line().to_int(),
    foreach (TC in 1..T)
        Text = read_line().to_array(),
        do_case(TC, Text)
    end.

do_case(TC, Text) =>
    S = to_array("welcome to code jam"),
    W = ways(Text, len(Text), S, len(S)),
    printf("Case #%w: %04d\n", TC, W).

table
ways(_, _, _, 0) = 1.
ways(_, 0, _, _) = 0.
ways(Text, I, S, J) = W =>
    if Text[I] == S[J] then
        W = (ways(Text, I - 1, S, J) + ways(Text, I - 1, S, J - 1)) mod 10000
    else
        W = ways(Text, I - 1, S, J)
    end.

picat-lang.org