cut.run

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cut.run

model cut.mod;
data cut.dat;
option solver cplex, solution_round 6;
option display_1col 0, display_transpose -10;

problem Cutting_Opt: Cut, Number, Fill;
option relax_integrality 1;

problem Pattern_Gen: Use, Reduced_Cost, Width_Limit;
option relax_integrality 0;

let nPAT := 0;
for {i in WIDTHS} {
   let nPAT := nPAT + 1;
   let nbr[i,nPAT] := floor (roll_width/i);
   let {i2 in WIDTHS: i2 <> i} nbr[i2,nPAT] := 0;
}

repeat {
   solve Cutting_Opt;
   let {i in WIDTHS} price[i] := Fill[i].dual;

   solve Pattern_Gen;
   if Reduced_Cost < -0.00001 then {
      let nPAT := nPAT + 1;
      let {i in WIDTHS} nbr[i,nPAT] := Use[i];
   }
   else break;
}
display nbr, Cut;

option Cutting_Opt.relax_integrality 0;
solve Cutting_Opt;
display Cut;