hdu1532（网络流）

#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 300
#define FILL(a,b) (memset(a,b,sizeof(a)))
#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;
    while(ch>‘9‘||ch<‘0‘)ch=getchar();
    while(ch<=‘9‘&&ch>=‘0‘){x=x*10+ch-‘0‘;ch=getchar();}
    return x;
}
int cap[N][N];
int flow[N][N];
int a[N],p[N];
int Ford_fulkerson(int s,int t)
{
    queue<int>que;
    FILL(flow,0);
    int f=0,u,v;
    while(1)
    {
        FILL(a,0);
        a[s]=inf;
        que.push(s);
        while(!que.empty())
        {
            u=que.front();que.pop();
            for(v=1;v<=t;v++)
            {
                if(!a[v]&&flow[u][v]<cap[u][v])
                {
                    p[v]=u;que.push(v);
                    a[v]=a[u]<cap[u][v]-flow[u][v]?a[u]:cap[u][v]-flow[u][v];
                }
            }
        }
        if(a[t]==0)return f;
        for(int i=t;i!=s;i=p[i])
        {
            flow[i][p[i]]-=a[t];
            flow[p[i]][i]+=a[t];
        }
        f+=a[t];
    }
}
int main()
{
    int n,m;
    while(scanf("%d%d",&n,&m)>0)
    {
        FILL(cap,0);
        for(int i=1;i<=n;i++)
        {
            int u,v,w;
            scanf("%d%d%d",&u,&v,&w);
            cap[u][v]+=w;
        }
        printf("%d\n",Ford_fulkerson(1,m));
    }
}