EdmondsKarp模板，hdu1532

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模板题。
#include<iostream>#include<string>#include<cstring>#include<cstdio>#include<cmath>#include<iomanip>#include<map>#include<algorithm>#include<queue>#include<set>#define inf 10000000#define pi acos(-1.0)#define eps 1e-8#define seed 131using namespace std;typedef pair<int,int> pii;typedef unsigned long long ULL;typedef long long LL;const int maxn=205;struct Edge{    int from,to,cap,flow;    Edge(int a,int b,int c,int d):from(a),to(b),cap(c),flow(d){}};int n,m;vector<Edge> edges;vector<int> g[maxn];int a[maxn];//可改进量int p[maxn];//最短路树上的入弧编号void init(){    for(int i=0;i<m;i++)        g[i].clear();    edges.clear();}void addEdge(int a,int b,int c){    edges.push_back(Edge(a,b,c,0));    edges.push_back(Edge(b,a,0,0));    int m=edges.size();    g[a].push_back(m-2);    g[b].push_back(m-1);}int maxFlow(int s,int t){    int flow=0;    for(;;)    {        memset(a,0,sizeof(a));        queue<int>que;        que.push(s);        a[s]=inf;        while(!que.empty())        {            int u=que.front();            que.pop();            int len=g[u].size();            for(int i=0;i<len;i++)            {                Edge& e=edges[g[u][i]];                if(!a[e.to]&&e.cap>e.flow)                {                    p[e.to]=g[u][i];                    a[e.to]=min(a[u],e.cap-e.flow);                    que.push(e.to);                }            }            if(a[t])                break;        }        if(a[t]==0)            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 a,b,c;    while(~scanf("%d%d",&n,&m))    {        init();        for(int i=0;i<n;i++)        {            scanf("%d%d%d",&a,&b,&c);            addEdge(a,b,c);        }        cout<<maxFlow(1,m)<<endl;    }    return 0;}
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