HDU1532 最大流-模板题

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题目是网络流-最大流的模板题

这里作为学习，把《指南》上Dinic的模板用了一下，代码如下：

#include <stdio.h>#include <iostream>#include <queue>#include <string.h>#include <vector>using namespace std;const int MAXN = 10000;const int INF = 0x3f3f3f3f;int min(int a, int b){    return a}struct Edge{    int from, to, cap, flow;    Edge(int a, int b, int c, int d): from(a), to(b), cap(c), flow(d) {}};struct Dinic {    int n, m, s, t;    vector edges;    vectorG[MAXN];    bool vis[MAXN];    int d[MAXN];    int cur[MAXN];    void AddEdge(){        int from, to, cap;        scanf("%d%d%d", &from, &to, &cap);        Edge tedge = Edge(from, to, cap, 0);        edges.push_back(tedge);        tedge = Edge(to, from, 0, 0);        edges.push_back(tedge);        int m = edges.size();        G[from].push_back(m-2);        G[to].push_back(m-1);    }       bool BFS() {        memset(vis, 0, sizeof(vis));        queueq;        q.push(s);        d[s] = 0;        vis[s] = 1;        while(!q.empty()){            int x = q.front();            q.pop();            for(int i=0; i                Edge &e = edges[G[x][i]];                if(!vis[e.to] && e.cap > e.flow){                    vis[e.to] = 1;                    d[e.to] = d[x] + 1;                    q.push(e.to);                }            }        }        return vis[t];    }    int DFS(int x, int a){        if(x==t || a==0) return a;        int flow = 0, f;        for(int& i=cur[x]; i            Edge& e = edges[G[x][i]];            if(d[x]+1==d[e.to] && (f=DFS(e.to, min(a, e.cap-e.flow))) > 0) {                e.flow += f;                edges[G[x][i]^1].flow -= f;                flow += f;                a -= f;                if(a==0) break;            }        }        return flow;    }    int Maxflow(int s, int t){        this->s = s;        this->t = t;        int flow = 0;        while(BFS()) {            memset(cur, 0, sizeof(cur));            flow += DFS(s, INF);        }        return flow;    }};int main(){//    freopen("in.txt", "r", stdin);    int n, m;    while(scanf("%d%d", &n, &m)!=EOF){        int i;        Dinic din;        for(i=0; i            din.AddEdge();        }        printf("%d\n", din.Maxflow(1, m));    }}