HDU - 3002 King of Destruction(最小割)

http://acm.hdu.edu.cn/showproblem.php?pid=3002

 

最小割模板

#include<iostream>
#include<cmath>
#include<cstring>
#include<queue>
#include<vector>
#include<cstdio>
#include<algorithm>
#include<map>
#include<set>
#define rep(i,e) for(int i=0;i<(e);i++)
#define rep1(i,e) for(int i=1;i<=(e);i++)
#define repx(i,x,e) for(int i=(x);i<=(e);i++)
#define X first
#define Y second
#define PB push_back
#define MP make_pair
#define mset(var,val) memset(var,val,sizeof(var))
#define scd(a) scanf("%d",&a)
#define scdd(a,b) scanf("%d%d",&a,&b)
#define scddd(a,b,c) scanf("%d%d%d",&a,&b,&c)
#define pd(a) printf("%d\n",a)
#define scl(a) scanf("%lld",&a)
#define scll(a,b) scanf("%lld%lld",&a,&b)
#define sclll(a,b,c) scanf("%lld%lld%lld",&a,&b,&c)
#define IOS ios::sync_with_stdio(false);cin.tie(0)

using namespace std;
typedef long long ll;
template <class T>
void test(T a){cout<<a<<endl;}
template <class T,class T2>
void test(T a,T2 b){cout<<a<<" "<<b<<endl;}
template <class T,class T2,class T3>
void test(T a,T2 b,T3 c){cout<<a<<" "<<b<<" "<<c<<endl;}
const int N = 1e6+10;
const int inf = 0x3f3f3f3f;
const ll INF = 0x3f3f3f3f3f3f3f3fll;
const ll mod = 1000000007;
int T;
void testcase(){
    printf("Case #%d: ",++T);
}
const int MAXN = 2500;
const int MAXM = 30;
int maz[MAXN][MAXN];
int v[MAXN],dist[MAXN];
bool visit[MAXN];
int n,m;
int StoerWagner(int n){
    int cut = inf;
    for(int i=0;i<n;i++) v[i]=i;
    while(n>1){
        int k=1,pre=0;
        for(int i=1;i<n;++i){
            dist[v[i]]=maz[v[0]][v[i]];
            if(dist[v[i]]>dist[v[k]]) k=i;
        }
        mset(visit,false);
        visit[v[0]]=true;
        for(int i=1;i<n;i++){
            if(i==n-1){
                cut=min(cut,dist[v[k]]);
                for(int j=0;j<n;j++){
                    maz[v[pre]][v[j]] += maz[v[j]][v[k]];
                    maz[v[j]][v[pre]] += maz[v[j]][v[k]];
                }
                v[k]=v[--n];
            }
            visit[v[k]]=true;
            pre = k,k=-1;
            for(int j=1;j<n;j++){
                if(!visit[v[j]]){
                    dist[v[j]] += maz[v[pre]][v[j]];
                    if(k==-1 || dist[v[k]]<dist[v[j]]) k=j;
                }
            }
        }
    }
    return cut;
}

int main() {
#ifdef LOCAL
    freopen("in.txt","r",stdin);
#endif // LOCAL
    int n,m;
    while(~scdd(n,m)){
        mset(maz,0);
        int x,y,w;
        for(int i=0;i<m;i++){
            scddd(x,y,w);
            maz[x][y]+=w;
            maz[y][x]+=w;
        }
        cout<<StoerWagner(n)<<endl;
    }
    return 0;
}

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转载自www.cnblogs.com/fht-litost/p/9281892.html