theme_park
``` ```
% theme_park.pi (in Picat)
% by N.F. Zhou, Jan. 2, 2015
% Qualification Round 2010
% Problem C. Theme Park
%
% to use: picat theme_park < input_file > output_file
%
main =>
foreach (TC in 1..T)
do_case(TC)
end.

do_case(TC) =>
initialize_table,
Q = {read_int() : _ in 1..N},
run(R,1,0,Amt,(Q,K)),
printf("Case #%w: %w\n",TC, Amt).

run(0,_I,Amt0,Amt,_QK) => Amt = Amt0.
run(R,I,Amt0,Amt,QK),R>=1000 =>
rides(1000,I,NextI,A,QK),
run(R-1000,NextI,Amt0+A,Amt,QK).
run(R,I,Amt0,Amt,QK) =>
ride(I,NextI,A,QK),
run(R-1,NextI,Amt0+A,Amt,QK).

table (+,+,-,-,nt)
rides(1,I,NextI,A,QK) =>
ride(I,NextI,A,QK).
rides(R,I,NextI,A,QK) =>
ride(I,I1,A1,QK),
rides(R-1,I1,NextI,A2,QK),
A = A1+A2.

% get people in the range [I,NextI) to form one ride
table (+,-,-,nt)
ride(I,NextI,A,QK) =>
ride_aux(I,I,NextI,0,A,QK).

ride_aux(I0,I,NextI,A0,A,QK@(Q,K)) =>
A1 = A0+Q[I],
(A1 =< K ->
I1 = I+1,
(I1 > len(Q) -> I2 = 1; I2 = I1),
(I2 == I0 ->    % nobody can ride again in one ride
NextI = I2, A = A1
;
ride_aux(I0,I2,NextI,A1,A,QK)
)
;
NextI = I,
A = A0
).
``````