model:
sets:
machine/1..4/:x,prepare,cost,ability;
endsets
data:
prepare=1000 980 800 700;
cost=20 24 16 28;
ability=900 1000 1200 1600;
enddata
min=@sum(machine:cost*x+prepare*@if(x#gt#0,1,0));
@sum(machine:x)=2000;
@for(machine:x<=ability);
@for(machine:@gin(x));
end