#include <ilcplex/cplex.h>
#include <stdlib.h>
#include <string.h>
 
#define NUMROWS    2
#define NUMCOLS    3
#define NUMNZ      6
 
int
main (int argc, char **argv)
{
   int       status = 0;
   CPXENVptr env = NULL;
   CPXLPptr  lp  = NULL;
 
   double   obj[NUMCOLS];
   double   lb[NUMCOLS];
   double   ub[NUMCOLS];
   double   x[NUMCOLS];
   int      rmatbeg[NUMROWS];
   int      rmatind[NUMNZ];
   double   rmatval[NUMNZ];
   double   rhs[NUMROWS];
   char     sense[NUMROWS];
 
   int      solstat;
   double   objval;
 
   env = CPXopenCPLEX (&status);
   if ( env == NULL ) {
      char  errmsg[1024];
      fprintf (stderr, "Could not open CPLEX environment.\n");
      CPXgeterrorstring (env, status, errmsg);
      fprintf (stderr, "%s", errmsg);
      goto TERMINATE;
   }
 
   lp = CPXcreateprob (env, &status, "lpex1");
   if ( lp == NULL ) {
      fprintf (stderr, "Failed to create LP.\n");
      goto TERMINATE;
   }
 
   CPXchgobjsen (env, lp, CPX_MAX);
 
       obj[0] = 1.0;      obj[1] = 2.0;           obj[2] = 3.0;
        lb[0] = 0.0;       lb[1] = 0.0;           lb[2]  = 0.0;
        ub[0] = 40.0;      ub[1] = CPX_INFBOUND;  ub[2]  = CPX_INFBOUND;
 
   status = CPXnewcols (env, lp, NUMCOLS, obj, lb, ub, NULL, NULL);
   if ( status ) {
      fprintf (stderr, "Failed to populate problem.\n");
      goto TERMINATE;
   }
 
   rmatbeg[0] = 0;
   rmatind[0] = 0;     rmatind[1] = 1;    rmatind[2] = 2;  sense[0] = 'L';
   rmatval[0] = -1.0;  rmatval[1] = 1.0;  rmatval[2] = 1.0;  rhs[0] = 20.0;
 
   rmatbeg[1] = 3;
   rmatind[3] = 0;    rmatind[4] = 1;    rmatind[5] = 2;     sense[1] = 'L';
   rmatval[3] = 1.0;  rmatval[4] = -3.0; rmatval[5] = 1.0;   rhs[1]   = 30.0;
 
   status = CPXaddrows (env, lp, 0, NUMROWS, NUMNZ, rhs, sense, rmatbeg,
                        rmatind, rmatval, NULL, NULL);
   if ( status ) {
      fprintf (stderr, "Failed to populate problem.\n");
      goto TERMINATE;
   }
 
   status = CPXlpopt (env, lp);
   if ( status ) {
      fprintf (stderr, "Failed to optimize LP.\n");
      goto TERMINATE;
   }
 
   status = CPXsolution (env, lp, &solstat, &objval, x, NULL, NULL, NULL);
   if ( status ) {
      fprintf (stderr, "Failed to obtain solution.\n");
      goto TERMINATE;
   }
   printf ("\nSolution status = %d\n", solstat);
   printf ("Solution value  = %f\n", objval);
   printf ("Solution        = [%f, %f, %f]\n\n", x[0], x[1], x[2]);
 
TERMINATE:
 
   if ( lp != NULL ) {
      status = CPXfreeprob (env, &lp);
      if ( status ) {
         fprintf (stderr, "CPXfreeprob failed, error code %d.\n", status);
      }
   }
 
   if ( env != NULL ) {
      status = CPXcloseCPLEX (&env);
      if ( status ) {
         char  errmsg[1024];
         fprintf (stderr, "Could not close CPLEX environment.\n");
         CPXgeterrorstring (env, status, errmsg);
         fprintf (stderr, "%s", errmsg);
      }
   }
 
   return (status);
 
}  /* END main */