题目大意：

明显的网络流问题，直接到魔板代码就可以ac，具体内容就不重复了，其实我看完样例数据根本就没读题。

代码：

#include<iostream>
#include<math.h>
#include<stdio.h>
#include<string.h>
#include<vector>
#include<queue>
#define maxn 2210
#define inf 0x3f3f3f3f
using namespace std;

struct Edge
{
    int from,to,cap,flow;
    Edge(int u,int v,int c,int f):from(u),to(v),cap(c),flow(f){}
};

int n;int m;
vector<Edge>edges;
vector<int>G[maxn];
int a[maxn];
int p[maxn];
void init(int n)
{
    for(int i=0;i<n;i++)G[i].clear();
    edges.clear();
}
void add_edge(int from,int to,int cap)
{
    edges.push_back(Edge(from,to,cap,0));
    edges.push_back(Edge(to,from,0,0));
    int lm=edges.size();
    G[from].push_back(lm-2);
    G[to].push_back(lm-1);
}
int maxflow(int s,int t)
{
    int flow=0;
    while(1)
    {
        memset(a,0,sizeof(a));
        queue<int>Q;
        Q.push(s);
        a[s]=inf;
        while(!Q.empty())
        {
            int x=Q.front();Q.pop();
            for(int i=0;i<G[x].size();i++)
            {
                Edge& e=edges[G[x][i]];
                if(!a[e.to]&&e.cap>e.flow)
                {
                    p[e.to]=G[x][i];
                    a[e.to]=min(a[x],e.cap-e.flow);
                    Q.push(e.to);
                }
            }
            if(a[t])break;
        }
        if(!a[t])break;
        for(int u=t;u!=s;u=edges[p[u]].from)
        {
            edges[p[u]].flow+=a[t];
            edges[p[u]^1].flow-=a[t];
        }
        flow+=a[t];
    }
    return flow;
}

int main()
{
    int test=0;
    cin>>test;
    for(int xcx=1;xcx<=test;xcx++)
    {
        scanf("%d%d",&n,&m);
        init(n);
        memset(p,0,sizeof(p));
        for(int i=1;i<=m;i++)
        {
            int la,lb,lc;
            scanf("%d%d%d",&la,&lb,&lc);
            add_edge(la,lb,lc);
        }
        printf("Case %d: %d\n",xcx,maxflow(1,n));
    }
}