最小割Stoer-Wagner算法模板hdu3691

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#include <stdio.h>#include <string.h>#include <iostream>#include <cctype>#include <string>#include <cmath>#include <algorithm>#include <queue>#include <set>#include <vector>#include <map>#define PR pair<int,int>#define MP make_pair#define fi first#define se second#define lson l,m,rt<<1#define rson m+1,r,rt<<1|1#define sqr(x) ((x)*(x))#define ll __int64const int M=21000;const int N=350;const int MOD=1000000007;const int INF=0x3f3f3f3f;const double eps=1e-10;const double pi=3.1415926536;using namespace std;int n,m,S,T;int mincut;int vis[N];int wet[N];int combine[N];int mp[N][N];void Search(){    int i,j,mx,tmp;    memset(vis,0,sizeof(vis));    memset(wet,0,sizeof(wet));    S=T=-1;    for(i=0;i<n;i++)    {        mx=-INF;        for(j=0;j<n;j++)        {            if(!combine[j]&&!vis[j]&&wet[j]>mx)            {                tmp=j;                mx=wet[j];            }        }        if(T==tmp) return;        S=T;T=tmp;        mincut=mx;        vis[tmp]=1;        for(j=0;j<n;j++)        {            if(!combine[j]&&!vis[j]) wet[j]+=mp[tmp][j];        }    }}int SW(){    int i,j;    memset(combine,0,sizeof(combine));    int ans=INF;    for(i=0;i<n-1;i++)    {        Search();        ans=min(ans,mincut);        if(ans==0) return 0;        combine[T]=1;        for(j=0;j<n;j++)        {            if(!combine[j])            {                mp[S][j]+=mp[T][j];                mp[j][S]+=mp[j][T];            }        }    }    return ans;}int main(){    //freopen("in.txt","r",stdin);    while(~scanf("%d%d%d",&n,&m,&S)&&n&&m&&S)    {        memset(mp,0,sizeof(mp));        for(int i=0;i<m;i++)        {            int u,v,w;            scanf("%d%d%d",&u,&v,&w);            u--;v--;            mp[u][v]+=w;            mp[v][u]+=w;        }        printf("%d\n",SW());    }}
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