diff -r d8475431bbbb -r 8e85e6bbefdf demo/lp_demo.cc
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/demo/lp_demo.cc	Mon May 23 04:48:14 2005 +0000
@@ -0,0 +1,113 @@
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <iostream>
+
+
+#ifdef HAVE_GLPK
+#include <lemon/lp_glpk.h>
+#elif HAVE_CPLEX
+#include <lemon/lp_cplex.h>
+#endif
+
+using namespace lemon;
+
+#ifdef HAVE_GLPK
+typedef LpGlpk LpDefault;
+#elif HAVE_CPLEX
+typedef LpCplex LpDefault;
+#endif
+
+int main()
+{     
+ //The following example is taken from the documentation of the GLPK library.
+ //See it in the GLPK reference manual and among the GLPK sample files (sample.c)
+  LpDefault lp;
+  typedef LpDefault::Row Row;
+  typedef LpDefault::Col Col;
+
+  lp.max();
+
+  Col x1 = lp.addCol();
+  Col x2 = lp.addCol();
+  Col x3 = lp.addCol();
+
+  //One solution
+  //   Row p = lp.addRow();
+  //   Row q = lp.addRow();
+  //   Row r = lp.addRow();
+  //   lp.setRow(p,x1+x2+x3 <=100);  
+  //   lp.setRow(q,10*x1+4*x2+5*x3<=600);  
+  //   lp.setRow(r,2*x1+2*x2+6*x3<=300);  
+
+  //A more elegant one
+  //Constraints
+  lp.addRow(x1+x2+x3 <=100);  
+  lp.addRow(10*x1+4*x2+5*x3<=600);  
+  lp.addRow(2*x1+2*x2+6*x3<=300);  
+  //Nonnegativity of the variables
+  lp.colLowerBound(x1, 0);
+  lp.colLowerBound(x2, 0);
+  lp.colLowerBound(x3, 0);
+  //Objective function
+  lp.setObj(10*x1+6*x2+4*x3);
+  
+  lp.solve();
+
+  if (lp.primalStatus()==LpSolverBase::OPTIMAL){
+    printf("Z = %g; x1 = %g; x2 = %g; x3 = %g\n", 
+	   lp.primalValue(), 
+	   lp.primal(x1), lp.primal(x2), lp.primal(x3));
+  }
+  else{
+    std::cout<<"Optimal solution not found!"<<std::endl;
+  }
+
+
+  //Here comes the same problem written in C using GLPK API routines
+
+//   LPX *lp;
+//       int ia[1+1000], ja[1+1000];
+//       double ar[1+1000], Z, x1, x2, x3;
+// s1:   lp = lpx_create_prob();
+// s2:   lpx_set_prob_name(lp, "sample");
+// s3:   lpx_set_obj_dir(lp, LPX_MAX);
+// s4:   lpx_add_rows(lp, 3);
+// s5:   lpx_set_row_name(lp, 1, "p");
+// s6:   lpx_set_row_bnds(lp, 1, LPX_UP, 0.0, 100.0);
+// s7:   lpx_set_row_name(lp, 2, "q");
+// s8:   lpx_set_row_bnds(lp, 2, LPX_UP, 0.0, 600.0);
+// s9:   lpx_set_row_name(lp, 3, "r");
+// s10:  lpx_set_row_bnds(lp, 3, LPX_UP, 0.0, 300.0);
+// s11:  lpx_add_cols(lp, 3);
+// s12:  lpx_set_col_name(lp, 1, "x1");
+// s13:  lpx_set_col_bnds(lp, 1, LPX_LO, 0.0, 0.0);
+// s14:  lpx_set_obj_coef(lp, 1, 10.0);
+// s15:  lpx_set_col_name(lp, 2, "x2");
+// s16:  lpx_set_col_bnds(lp, 2, LPX_LO, 0.0, 0.0);
+// s17:  lpx_set_obj_coef(lp, 2, 6.0);
+// s18:  lpx_set_col_name(lp, 3, "x3");
+// s19:  lpx_set_col_bnds(lp, 3, LPX_LO, 0.0, 0.0);
+// s20:  lpx_set_obj_coef(lp, 3, 4.0);
+// s21:  ia[1] = 1, ja[1] = 1, ar[1] =  1.0; /* a[1,1] =  1 */
+// s22:  ia[2] = 1, ja[2] = 2, ar[2] =  1.0; /* a[1,2] =  1 */
+// s23:  ia[3] = 1, ja[3] = 3, ar[3] =  1.0; /* a[1,3] =  1 */
+// s24:  ia[4] = 2, ja[4] = 1, ar[4] = 10.0; /* a[2,1] = 10 */
+// s25:  ia[5] = 3, ja[5] = 1, ar[5] =  2.0; /* a[3,1] =  2 */
+// s26:  ia[6] = 2, ja[6] = 2, ar[6] =  4.0; /* a[2,2] =  4 */
+// s27:  ia[7] = 3, ja[7] = 2, ar[7] =  2.0; /* a[3,2] =  2 */
+// s28:  ia[8] = 2, ja[8] = 3, ar[8] =  5.0; /* a[2,3] =  5 */
+// s29:  ia[9] = 3, ja[9] = 3, ar[9] =  6.0; /* a[3,3] =  6 */
+// s30:  lpx_load_matrix(lp, 9, ia, ja, ar);
+// s31:  lpx_simplex(lp);
+// s32:  Z = lpx_get_obj_val(lp);
+// s33:  x1 = lpx_get_col_prim(lp, 1);
+// s34:  x2 = lpx_get_col_prim(lp, 2);
+// s35:  x3 = lpx_get_col_prim(lp, 3);
+// s36:  printf("\nZ = %g; x1 = %g; x2 = %g; x3 = %g\n", Z, x1, x2, x3);
+// s37:  lpx_delete_prob(lp);
+//       return 0;
+
+  return 0;
+}