/********************************************************
  Xpress-BCL Java Example Problems
  ================================

  file xbcontr.java
  `````````````````
  Contract allocation example.

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

import java.io.*;
import com.dashoptimization.*;

public class xbcontr {
    static final int District = 6;   /* Number of districts */
    static final int Contract = 10;  /* Number of contracts */

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

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

    public static void main(String[] args) throws IOException {
        int d,c;
        XPRB bcl;
        XPRBexpr l1,l2,lobj;
        XPRBvar[][] x;                  /* Variables indicating whether a project
                                           is chosen */
        XPRBvar[][] y;                  /* Quantities allocated to contractors */

        try (XPRBprob p = new XPRBprob("Contract")) { /* Initialize BCL create a new problem */

            /**** VARIABLES ****/
            x = new XPRBvar[District][Contract];
            y = new XPRBvar[District][Contract];
            for(d=0;d<District;d++) for(c=0;c<Contract;c++) x[d][c]=p.newVar("x_d"+ y[d][c]=p.newVar("q_d"+ lobj=new for(d=0;d<District;d++) Set the objective function CONSTRAINTS l1=new l2=new /*="Size" : cover req. volume at least districts contract Do not exceed max. output If a is allocated to then unit it Output matrix in MPS format Choose sense of optimization Solve MIP-problem if((p.getMIPStat()==XPRB.MIP_SOLUTION) (p.getMIPStat()==XPRB.MIP_OPTIMAL)) Test whether an integer sol. was found>0)
                                System.out.print(y[d][c].getName() + ":" + y[d][c].getSol() + ", ");
                        System.out.println();
                    }
                }
        }
    }
}