/********************************************************
  BCL Example Problems
  ====================

  file xbcontr.c
  ``````````````
  Contract allocation example.

  (c) 2008-2023 Fair Isaac Corporation
      author: S.Heipcke, Jan. 2000, rev. Mar. 2011
********************************************************/

#include <stdio.h>
#include "xprb.h"

#define District 6                 /* Number of districts */
#define Contract 10                /* Number of contracts */

/**** DATA ****/
int OUTPUT[] = {50, 40, 10, 20, 70, 50};    /* Max. output per district */
int COST[]   = {50, 20, 25, 30, 45, 40};    /* Cost per district */
int VOLUME[]   = {20, 10, 30, 15, 20, 30, 10, 50, 10, 20};
                                   /* Volume of contracts */

/***********************************************************************/

int main(int argc, char **argv)
{
 int d,c;
 XPRBctr c1,c2,cobj;
 XPRBvar x[District][Contract];    /* Variables indicating whether a project
                                      is chosen */
 XPRBvar y[District][Contract];    /* Quantities allocated to contractors */
 XPRBprob prob;

 prob=XPRBnewprob("Contract");     /* Initialize a new problem in BCL */

/**** VARIABLES ****/
 for(d=0;d<District;d++) for(c=0;c<Contract;c++) x[d][c]=XPRBnewvar(prob,XPRB_BV,XPRBnewname("x_d%dc%d",d+1,c+1),0,1); y[d][c]=XPRBnewvar(prob,XPRB_SC,XPRBnewname("q_d%dc%d",d+1,c+1),0,OUTPUT[d]); cobj=XPRBnewctr(prob,"OBJ",XPRB_N); Define objective: total cost for(d=0;d<District;d++) Set objective function CONSTRAINTS c1=XPRBnewctr(prob,"Size",XPRB_G); Cover the required contract volume c2=XPRBnewctr(prob,"Min",XPRB_G); At least districts per Do not exceed max. output of any district If a is allocated to then at unit it Output matrix in MPS format Choose sense optimization Solve MIP-problem if((XPRBgetmipstat(prob)==XPRB_MIP_SOLUTION) (XPRBgetmipstat(prob)==XPRB_MIP_OPTIMAL)) Test whether an integer solution was found Get value Print values>0)
     printf("%s:%g, ", XPRBgetvarname(y[d][c]), XPRBgetsol(y[d][c]));
   printf("\n");
  }
 }
 return 0;
}