marci@1017: // -*- c++ -*-
marci@1017: #ifndef LEMON_MIN_COST_GEN_FLOW_H
marci@1017: #define LEMON_MIN_COST_GEN_FLOW_H
marci@1025: #include <iostream>
marci@1017: //#include <fstream>
marci@1017: 
marci@1025: #include <lemon/smart_graph.h>
marci@1025: #include <lemon/list_graph.h>
marci@1017: //#include <lemon/dimacs.h>
marci@1017: //#include <lemon/time_measure.h>
marci@1017: //#include <graph_wrapper.h>
marci@1025: #include <lemon/preflow.h>
marci@1017: //#include <augmenting_flow.h>
marci@1017: //#include <preflow_res.h>
marci@1025: #include <../merge_node_graph_wrapper.h>
marci@1017: #include <lemon/../work/marci/lp/lp_solver_wrapper.h>
marci@1017: 
marci@1017: namespace lemon {
marci@1017: 
marci@1017:   template<typename Edge, typename EdgeIndexMap> 
marci@1017:   class PrimalMap {
marci@1017:   protected:
marci@1017:     LPSolverWrapper* lp;
marci@1017:     EdgeIndexMap* edge_index_map;
marci@1017:   public:
marci@1017:     PrimalMap(LPSolverWrapper& _lp, EdgeIndexMap& _edge_index_map) : 
marci@1017:       lp(&_lp), edge_index_map(&_edge_index_map) { }
marci@1017:     double operator[](Edge e) const { 
marci@1017:       return lp->getPrimal((*edge_index_map)[e]);
marci@1017:     }
marci@1017:   };
marci@1017: 
marci@1017:   // excess: rho-delta
marci@1017:   template <typename Graph, typename Num,
marci@1017: 	    typename Excess=typename Graph::template NodeMap<Num>, 
marci@1017: 	    typename LCapMap=typename Graph::template EdgeMap<Num>,
marci@1017: 	    typename CapMap=typename Graph::template EdgeMap<Num>,
marci@1017:             typename FlowMap=typename Graph::template EdgeMap<Num>,
marci@1017: 	    typename CostMap=typename Graph::template EdgeMap<Num> >
marci@1017:   class MinCostGenFlow {
marci@1017:   protected:
marci@1017:     const Graph& g;
marci@1017:     const Excess& excess;
marci@1017:     const LCapMap& lcapacity;
marci@1017:     const CapMap& capacity;
marci@1017:     FlowMap& flow;
marci@1017:     const CostMap& cost;
marci@1017:   public:
marci@1017:     MinCostGenFlow(const Graph& _g, const Excess& _excess, 
marci@1017: 		   const LCapMap& _lcapacity, const CapMap& _capacity, 
marci@1017: 		   FlowMap& _flow, 
marci@1017: 		   const CostMap& _cost) :
marci@1017:       g(_g), excess(_excess), lcapacity(_lcapacity),
marci@1017:       capacity(_capacity), flow(_flow), cost(_cost) { }
marci@1025:     bool feasible() {
marci@1025:       //      std::cout << "making new vertices..." << std::endl; 
marci@1025:       typedef ListGraph Graph2;
marci@1025:       Graph2 g2;
marci@1025:       typedef MergeEdgeGraphWrapper<const Graph, Graph2> GW;
marci@1025:       //      std::cout << "merging..." << std::endl; 
marci@1025:       GW gw(g, g2);
marci@1025:       typename GW::Node s(INVALID, g2.addNode(), true);
marci@1025:       typename GW::Node t(INVALID, g2.addNode(), true);
marci@1025:       typedef SmartGraph Graph3;
marci@1025:       //      std::cout << "making extender graph..." << std::endl; 
marci@1025:       typedef NewEdgeSetGraphWrapper2<GW, Graph3> GWW;
marci@1025: //       {
marci@1025: // 	checkConcept<StaticGraph, GWW>();   
marci@1025: //       }
marci@1025:       GWW gww(gw);
marci@1025:       typedef AugmentingGraphWrapper<GW, GWW> GWWW;
marci@1025:       GWWW gwww(gw, gww);
marci@1025: 
marci@1025:       //      std::cout << "making new edges..." << std::endl; 
marci@1025:       typename GWWW::template EdgeMap<Num> translated_cap(gwww);
marci@1025: 
marci@1025:       for (typename GW::EdgeIt e(gw); e!=INVALID; ++e)
marci@1025:       translated_cap.set(typename GWWW::Edge(e,INVALID,false), 
marci@1025: 			 capacity[e]-lcapacity[e]);
marci@1025: 
marci@1025:       Num expected=0;
marci@1025: 
marci@1025:       //      std::cout << "making new edges 2..." << std::endl; 
marci@1025:       for (typename Graph::NodeIt n(g); n!=INVALID; ++n) {
marci@1025: 	Num a=0;
marci@1025: 	for (typename Graph::InEdgeIt e(g, n); e!=INVALID; ++e)
marci@1025: 	  a+=lcapacity[e];
marci@1025: 	for (typename Graph::OutEdgeIt e(g, n); e!=INVALID; ++e) 
marci@1025: 	  a-=lcapacity[e];
marci@1025: 	if (excess[n]>a) {
marci@1025: 	  typename GWW::Edge e=
marci@1025: 	    gww.addEdge(typename GW::Node(n,INVALID,false), t);
marci@1025: 	  translated_cap.set(typename GWWW::Edge(INVALID, e, true), 
marci@1025: 			     excess[n]-a);
marci@1025: 	}
marci@1025: 	if (excess[n]<a) {
marci@1025: 	  typename GWW::Edge e=
marci@1025: 	    gww.addEdge(s, typename GW::Node(n,INVALID,false));
marci@1025: 	  translated_cap.set(typename GWWW::Edge(INVALID, e, true), 
marci@1025: 			     a-excess[n]);
marci@1025: 	  expected+=a-excess[n];
marci@1025: 	}
marci@1025:       }
marci@1025: 
marci@1025:       //      std::cout << "preflow..." << std::endl; 
marci@1025:       typename GWWW::template EdgeMap<Num> translated_flow(gwww, 0);
marci@1025:       Preflow<GWWW, Num> preflow(gwww, s, t, 
marci@1025: 				 translated_cap, translated_flow);
marci@1025:       preflow.run();
marci@1025:       //      std::cout << "fv: " << preflow.flowValue() << std::endl; 
marci@1025:       //      std::cout << "expected: " << expected << std::endl; 
marci@1025: 
marci@1025:       for (typename Graph::EdgeIt e(g); e!=INVALID; ++e) {
marci@1025: 	typename GW::Edge ew(e, INVALID, false);
marci@1025: 	typename GWWW::Edge ewww(ew, INVALID, false);
marci@1025: 	flow.set(e, translated_flow[ewww]+lcapacity[e]);
marci@1025:       }
marci@1025:       return (expected>=preflow.flowValue());
marci@1025:     }
marci@1017:     void run() {
marci@1017:       LPSolverWrapper lp;
marci@1017:       lp.setMinimize();
marci@1017:       typedef LPSolverWrapper::ColIt ColIt;
marci@1017:       typedef LPSolverWrapper::RowIt RowIt;
marci@1017:       typedef typename Graph::template EdgeMap<ColIt> EdgeIndexMap;
marci@1017:       EdgeIndexMap edge_index_map(g);
marci@1017:       PrimalMap<typename Graph::Edge, EdgeIndexMap> lp_flow(lp, edge_index_map);
marci@1017:       for (typename Graph::EdgeIt e(g); e!=INVALID; ++e) {
marci@1017: 	ColIt col_it=lp.addCol();
marci@1017: 	edge_index_map.set(e, col_it);
marci@1017: 	if (lcapacity[e]==capacity[e])
marci@1017: 	  lp.setColBounds(col_it, LPX_FX, lcapacity[e], capacity[e]);
marci@1017: 	else 
marci@1017: 	  lp.setColBounds(col_it, LPX_DB, lcapacity[e], capacity[e]);
marci@1017: 	lp.setObjCoef(col_it, cost[e]);
marci@1017:       }
marci@1017:       for (typename Graph::NodeIt n(g); n!=INVALID; ++n) {
marci@1017: 	typename Graph::template EdgeMap<Num> coeffs(g, 0);
marci@1017: 	for (typename Graph::InEdgeIt e(g, n); e!=INVALID; ++e)
marci@1017: 	coeffs.set(e, coeffs[e]+1);
marci@1017: 	for (typename Graph::OutEdgeIt e(g, n); e!=INVALID; ++e) 
marci@1017: 	coeffs.set(e, coeffs[e]-1);
marci@1017: 	RowIt row_it=lp.addRow();
marci@1017: 	typename std::vector< std::pair<ColIt, double> > row;
marci@1017: 	//std::cout << "node:" <<g.id(n)<<std::endl;
marci@1017: 	for (typename Graph::EdgeIt e(g); e!=INVALID; ++e) {
marci@1017: 	  if (coeffs[e]!=0) {
marci@1017: 	    //std::cout << " edge:" <<g.id(e)<<" "<<coeffs[e];
marci@1017: 	    row.push_back(std::make_pair(edge_index_map[e], coeffs[e]));
marci@1017: 	  }
marci@1017: 	}
marci@1017: 	//std::cout << std::endl;
marci@1017: 	lp.setRowCoeffs(row_it, row.begin(), row.end());
marci@1017: 	lp.setRowBounds(row_it, LPX_FX, 0.0, 0.0);
marci@1017:       }
marci@1017:       lp.solveSimplex();
marci@1017:       //std::cout << lp.colNum() << std::endl;
marci@1017:       //std::cout << lp.rowNum() << std::endl;
marci@1017:       //std::cout << "flow value: "<< lp.getObjVal() << std::endl;
marci@1017:       for (typename Graph::EdgeIt e(g); e!=INVALID; ++e) 
marci@1017:       flow.set(e, lp_flow[e]);
marci@1017:     }
marci@1017:   };
marci@1017: 
marci@1017: } // namespace lemon
marci@1017: 
marci@1017: #endif //LEMON_MIN_COST_GEN_FLOW_H