demo/mip_demo.cc
author deba
Tue, 21 Aug 2007 13:22:21 +0000
changeset 2463 19651a04d056
parent 2369 6ae1a97055a2
child 2492 387f6ff851ef
permissions -rw-r--r--
Query functions: aMatching and bMatching
Modified algorithm function interfaces
ANodeMap<UEdge> matching map
BNodeMap<bool> barrier map

Consistency between augmenting path and push-relabel algorithm
     1 /* -*- C++ -*-
     2  *
     3  * This file is a part of LEMON, a generic C++ optimization library
     4  *
     5  * Copyright (C) 2003-2007
     6  * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
     7  * (Egervary Research Group on Combinatorial Optimization, EGRES).
     8  *
     9  * Permission to use, modify and distribute this software is granted
    10  * provided that this copyright notice appears in all copies. For
    11  * precise terms see the accompanying LICENSE file.
    12  *
    13  * This software is provided "AS IS" with no warranty of any kind,
    14  * express or implied, and with no claim as to its suitability for any
    15  * purpose.
    16  *
    17  */
    18 
    19 #include <lemon/lp.h>
    20 //#include <lemon/ilp_glpk.h>
    21 
    22 using namespace lemon;
    23 
    24 int main(){
    25 
    26   //MipGlpk ilp;
    27 
    28    Mip ilp;
    29 
    30 
    31   typedef Mip::Row Row;
    32   typedef Mip::Col Col;
    33   
    34   ilp.max();
    35   
    36   Col x1 = ilp.addCol();
    37   Col x2 = ilp.addCol();
    38   Col x3 = ilp.addCol();
    39   
    40   ilp.integer(x1,true);
    41   ilp.integer(x2,true);
    42   ilp.integer(x3,true);
    43   
    44   ilp.addRow(x1+x2+x3 <=100);  
    45   ilp.addRow(10*x1+4*x2+5*x3<=600);  
    46   ilp.addRow(2*x1+2*x2+6*x3<=300); 
    47   
    48   ilp.colLowerBound(x1, 0);
    49   ilp.colLowerBound(x2, 0);
    50   ilp.colLowerBound(x3, 0);
    51   //Objective function
    52   ilp.obj(10*x1+6*x2+4*x3);
    53   
    54   //Call the routine of the underlying LP solver
    55   ilp.solve();
    56   
    57   //Print results
    58   if (ilp.primalStatus()==LpSolverBase::OPTIMAL){
    59     std::cout<<"Optimal solution found!"<<std::endl;
    60     printf("optimum value = %g; x1 = %g; x2 = %g; x3 = %g\n", 
    61            ilp.primalValue(), 
    62            ilp.primal(x1), ilp.primal(x2), ilp.primal(x3));
    63   }
    64   else{
    65     std::cout<<"Optimal solution not found!"<<std::endl;
    66   }
    67 
    68 }