double solve()
{
int i, j;
double ret;
make_net();
ret = Edmonds_Karp();
return exp(ret);
}
//利用找出的最大流，从中找出一个最小割（adjacency matrix）
void find_min_cut ( int s , int t )
{
Edmonds_Karp ( s , t );
memset ( visit , false , sizeof ( visit ));
DFS ( s );
for ( int i = 0 ; i < 10 ; ++ i ) //穷举源点侧的点
if ( visit [ i ])
for ( int j = 0 ; j < 10 ; ++ j ) //穷举汇点侧的点
if (! visit [ j ])
if ( C [ i ][ j ] > 0 ) //要确定有边
cout << "Cut上的边有"
<< "由" << i << "到" << j << endl ;
}
int main()
{
int n,m;
int u,v,c;
while(cin>>n>>m)
{
for(int i = 0; i < MAXN; i++)
Map[i].clear();
n_edge=0;
for(int i = 0; i < n; i++)
{
cin>>u>>v>>c; u--; v--;
if(c>0)
addEdge(u,v,c,0);
}
cout<<Edmonds_Karp(0,m-1)<<endl;
}
return 0;
}
int CFordFulkson::RunFF()
{
int i = 0;
int _min = 0;
int total = 0;
while(true)
{
if(!Edmonds_Karp())
{
// 进来就表示没有找到增广路径
// 为每条链路找到上一条链路
POSITION pos = pLinkList->GetHeadPosition();
while (pos != NULL)
{
CLink* pLink = (CLink*)pLinkList->GetAt(pos);
if (pLink->nShared % 2 == 1)
{
POSITION pos2 = pLinkList->GetHeadPosition();
bool bNeedExit = false;
while (pos2 != NULL)
{
CLink* pPreLink = (CLink*)pLinkList->GetAt(pos2);
if ((pPreLink->nShared % 2 == 1) && pPreLink->nEndAt == pLink->nStartAt)
{
bool bFind = false;
for (int k=0; k<pLink->nInputLink; k++)
{
if (pLink->nPreLink[k] == pPreLink->nLinkNum)
{
bFind = TRUE;
break;
}
}
if (bFind == TRUE)
{
bNeedExit = true;
}
else
{
int n = pLink->nInputLink;
pLink->nPreLink[n] = pPreLink->nLinkNum;
pLink->nInputLink++;
bNeedExit = true;
}
}
if (bNeedExit == TRUE)
{
break;
}
else
{
pLinkList->GetNext(pos2);
}
}
}
pLinkList->GetNext(pos);
}
// 此时nShared为奇数表示到该汇聚节点最大流时用到的链路
pos = pLinkList->GetHeadPosition();
int nRouteNum = 0;
while (pos != NULL)
{
CLink* pLink = (CLink*)pLinkList->GetAt(pos);
if (pLink->nStartAt == nSrc && pLink->nShared%2 == 1 && pLink->bAddToRouteTable == FALSE) // 起点为源节点
{
// Output the route array to the sink node
int nCurPos = nSrc;
int nHopNum = 0;
Route[nRouteNum][nHopNum++] = pLink->nLinkNum;
CLink *pPre_link = pLink;
while(1)
{
POSITION next_pos = pLinkList->GetHeadPosition();
while (next_pos != NULL)
{
CLink* pNextLink = (CLink*)pLinkList->GetAt(next_pos);
if (pNextLink->nStartAt == pPre_link->nEndAt && pNextLink->bAddToRouteTable == FALSE && pNextLink->nShared%2 == 1)
{
Route[nRouteNum][nHopNum++] = pNextLink->nLinkNum;
pNextLink->bAddToRouteTable = TRUE;
pPre_link = pNextLink;
break;
}
pLinkList->GetNext(next_pos);
}
if (pPre_link->nEndAt == nDes)
{
break;
}
}
nRouteNum++;
}
pLinkList->GetNext(pos);
}
// 将必要的链路标记出来
pos = pLinkList->GetHeadPosition();
while (pos != NULL)
{
CLink* pLink = (CLink*)pLinkList->GetAt(pos);
if (pLink->nShared % 2 == 1)
{
pLink->bInSubGraph = TRUE;
}
pLink->nShared = 0;
pLink->bAddToRouteTable = FALSE; // Reset
pLinkList->GetNext(pos);
}
return total;; //如果找不到增广路就返回，在具体实现时替换函数名
}
_min = (1<<30);
int des = nDes - 1;
int src = nSrc - 1;
i = des;
while(i != src)
{ //通过pre数组查找增广路径上的边，求出残留容量的最小值
if(_min > C[PreNode[i]][i])
{
_min=C[PreNode[i]][i];
}
i = PreNode[i];
}
i = des;
while (i != src)
{ //再次遍历，更新增广路径上边的流值
C[PreNode[i]][i] -= _min;
C[i][PreNode[i]] += _min;
i = PreNode[i];
}
total += _min; //每次加上更新的值
// Record the route
int nHops = 0;
i = des;
int routeTemp[20];
routeTemp[0] = des;
while ( TRUE )
{
if (PreNode[i] == src)
{
nHops++;
routeTemp[nHops] = PreNode[i];
i= PreNode[i];
break;
}
else
{
nHops++;
routeTemp[nHops] = PreNode[i];
i= PreNode[i];
}
}
// Reverse the route, and store it into Routes array.
// for (i=0; i<nHops; i++)
// {
// Route[total-1][i] = routeTemp[nHops-1-i];
// }
for (i=0; i<nHops; i++)
{
int nCnt = pLinkList->GetCount();
POSITION pos = pLinkList->GetHeadPosition();
while (pos != NULL)
{
// Both direction is ok.
CLink* pLink = (CLink*)pLinkList->GetAt(pos);
// Since the number of node start with 1, but the index in the array starts with 0,
// So we must decrease 1.
if (pLink->nStartAt-1 == routeTemp[i] && pLink->nEndAt-1 == routeTemp[i+1])
{
pLink->nShared = pLink->nShared+1;
}
// OR
if (pLink->nEndAt-1 == routeTemp[i] && pLink->nStartAt-1 == routeTemp[i+1])
{
pLink->nShared = pLink->nShared+1;
}
pLinkList->GetNext(pos);
}
}
}
//
}
