#ifndef FLOWEDGE_H_INCLUDED

#define FLOWEDGE_H_INCLUDED

#include"func.h"

/*

maxFlow最大流问题

相比较无向图Edge,添加两个变量和两个API

*/

class FlowEdge{

private:

int V; //边的起点

int W;

double capacity;

double flow; //实际流量

public:

FlowEdge():V(0),W(0),capacity(0.0){}

FlowEdge(int v,int w,double c)

:V(v),W(w),capacity(c),flow(0.0){}

//边的剩余容量 传入参数是边的enpoint

double residualCapacityTo(int vertex){

if(vertex==V) return flow; //backward edge

else if(vertex==W) return capacity-flow; //forward edge

return (double)-1;

}

//增加流量 传入参数是边的终点

void addResidualFlowTo(int vertex, double delta){

if(vertex==V) flow -= delta; //反向边

else if(vertex==W) flow+=delta; //正向边

}

//其它API

int from()const {return V;}

int to()const {return W;}

double getCapacity()const {return capacity;}

double getFlow(){return flow;}

int other(int vertex){

if(vertex==V) return W;

if(vertex==W) return V;

return -1;

}

void setFlow(double delta){flow += delta;}

bool operator==(const FlowEdge& that){return V==that.from() && W==that.to() && capacity==that.getCapacity();}

};

#endif // FLOWEDGE_H_INCLUDED