poj1459（最大流）

#pragma comment(linker,"/STACK:1024000000,1024000000")
#include <cstdio>
#include <cstring>
#include <string>
#include <cmath>
#include <limits.h>
#include <iostream>
#include <algorithm>
#include <queue>
#include <cstdlib>
#include <stack>
#include <vector>
#include <set>
#include <map>
#define LL long long
#define mod 100000000
#define inf 0x3f3f3f3f
#define eps 1e-6
#define N 510
#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1
#define PII pair<int,int>
using namespace std;
inline int read()
{
    char ch=getchar();
    int x=0,f=1;
    while(ch>‘9‘||ch<‘0‘){if(ch==‘-‘)f=-1;ch=getchar();}
    while(ch<=‘9‘&&ch>=‘0‘){x=x*10+ch-‘0‘;ch=getchar();}
    return x*f;
}
int n,m,np,nc,k,vs,vt,tot;
int pre[N],q[N],cur[N],h[N];
struct edge
{
    int v,w,next;
    edge(){}
    edge(int v,int w,int next):v(v),w(w),next(next){}
}e[N*N];
void addedge(int u,int v,int w)
{
    e[tot]=edge(v,w,pre[u]);
    pre[u]=tot++;
    e[tot]=edge(u,0,pre[v]);
    pre[v]=tot++;
}
void init()
{
    memset(pre,-1,sizeof(pre));
    tot=0;
}
/*******************dinic************************/
int bfs()
{
    int head=0,tail=1;
    memset(h,-1,sizeof(h));
    q[0]=vs;h[vs]=0;
    while(head!=tail)
    {
        int u=q[head++];
        for(int i=pre[u];~i;i=e[i].next)
        {
            int v=e[i].v,w=e[i].w;
            if(w&&h[v]==-1)
            {
                h[v]=h[u]+1;
                q[tail++]=v;
            }
        }
    }
    return h[vt]!=-1;
}
int dfs(int u,int flow)
{
    if(u==vt)return flow;
    int used=0;
    for(int i=cur[u];~i;i=e[i].next)
    {
        int v=e[i].v,w=e[i].w;
        if(h[v]==h[u]+1)
        {
            w=dfs(v,min(flow-used,w));
            e[i].w-=w;e[i^1].w+=w;
            if(e[i].w)cur[u]=i;
            used+=w;
            if(used==flow)return flow;
        }
    }
    if(!used)h[u]=-1;
    return used;
}
int dinic()
{
    int res=0;
    while(bfs())
    {
        for(int i=vs;i<=vt;i++)cur[i]=pre[i];
        res+=dfs(vs,inf);
    }
    return res;
}
/********************dinic***********************/
void build()
{
    int u,v,w;
    vs=0;vt=n+1;
    for(int i=1;i<=m;i++)
    {
        scanf(" (%d,%d)%d",&u,&v,&w);
        addedge(u+1,v+1,w);
    }
    for(int i=1;i<=np;i++)
    {
        scanf(" (%d)%d",&v,&w);
        addedge(vs,v+1,w);
    }
    for(int i=1;i<=nc;i++)
    {
        scanf(" (%d)%d",&u,&w);
        addedge(u+1,vt,w);
    }
}
int main()
{
    while(scanf("%d%d%d%d",&n,&np,&nc,&m)>0)
    {
        init();
        build();
        printf("%d\n",dinic());
    }
}