% Knapsack benchmark; adopted from:
%
% A. Dovier, A. Formisano, and E. Pontelli:
%    "A Comparison of CLP(FD) and ASP Solutions to NP-complete Problems"
% in Convegno Italiano di Logica Computazionale, June 2005.

#option -dnone

item(1..10).

#weight size(1,X1)=2*X1.
#weight size(2,X2)=4*X2.
#weight size(3,X3)=8*X3.
#weight size(4,X4)=16*X4.
#weight size(5,X5)=32*X5.
#weight size(6,X6)=64*X6.
#weight size(7,X7)=128*X7.
#weight size(8,X8)=256*X8.
#weight size(9,X9)=512*X9.
#weight size(10,X10)=1024*X10.

#weight cost(1,X1)=2*X1.
#weight cost(2,X2)=5*X2.
#weight cost(3,X3)=11*X3.
#weight cost(4,X4)=23*X4.
#weight cost(5,X5)=47*X5.
#weight cost(6,X6)=95*X6.
#weight cost(7,X7)=191*X7.
#weight cost(8,X8)=383*X8.
#weight cost(9,X9)=767*X9.
#weight cost(10,X10)=1535*X10.

occs(0..max_size).
1 { in_sack(I,XI):occs(XI) } 1 :- item(I).
size(I,XI) :- item(I), occs(XI), in_sack(I,XI).
cost(I,XI) :- item(I), occs(XI), in_sack(I,XI).
cond_cost :- min_profit [ cost(I,XI):item(I):occs(XI) ].
:- not cond_cost.
cond_weight :- [ size(I,XI):item(I):occs(XI) ] max_size.
:- not cond_weight.

#hide cond_weight, cond_cost.
#hide item(I).
#hide occs(X).
#hide size(I,S).
#hide cost(I,C).