杭电1532----Drainage Ditches『最大流』

/*
网络流的最大流问题
刚学习Dinic算法。模版题
 */
#include <cstring>
#include <cstdio>
#include <queue>
using namespace std;
const int maxn = 205;
const int inf = 0x3f3f3f3f;
struct
{
    int c,f;
}edge[maxn][maxn];
int dis[maxn];
int v,e;
bool bfs()
{
    memset(dis,0,sizeof dis);
    queue<int> q;
    q.push(1);
    dis[1] = 1;
    while(!q.empty())
    {
        int u = q.front(); q.pop();
        for(int i = 1; i <= v; ++i)
            if(!dis[i] && edge[u][i].c > edge[u][i].f)
            {dis[i] = dis[u] + 1;q.push(i);}
    }
    return dis[v] != 0;
}
int dfs(int u,int c)
{
    if(u == v) return c;
    int temp = c;
    for(int i = 1; i <= v && temp; ++i)
    {
        if(dis[i] != dis[u] + 1 || edge[u][i].c <= edge[u][i].f) continue;
        int t = dfs(i,min(temp,edge[u][i].c - edge[u][i].f));
        edge[u][i].f += t; edge[i][u].f -= t; temp -= t;
    }
    return c - temp;
}
int dinic()
{
    int ans = 0;
    while(bfs())
        while(int t = dfs(1,inf))
            ans += t;
    return ans;
}
int main()
{
    while(~scanf("%d%d",&e,&v))
    {
        memset(edge,0,sizeof edge);
        while(e--)
        {
            int x,y,z;
            scanf("%d%d%d",&x,&y,&z);
            edge[x][y].c += z;
        }
        int ans = dinic();
        printf("%d
",ans);
    }
    return 0;
}