[PA2014]Fiolki

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Solution 

正解是并查集重构树

可是我的启发式(set)合并(O(klog^2 n))也过了吖

Code 

#include<bits/stdc++.h>
#define ll long long
#define db double
#define dbg1(x) void(0)
#define dbg2(x) void(0)
#define dbg3(x) void(0)
using namespace std;
inline int read()
{
    int f=1,x=0;char ch=getchar();
    while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}
    while(ch>='0'&&ch<='9'){x=(x<<1)+(x<<3)+ch-'0';ch=getchar();}
    return x*f;
}
const int MN=2e5+5;
#define P pair<int,int>
#define mp make_pair
#define pb push_back
set<P> S[MN];ll ans;
int N,M,K,c[MN],lie[MN];
vector<int> G[MN];
vector<pair<int,int> >H[MN];
vector<pair<P,int> > z;
set<P>::iterator it,ii,jj;
int Cb(int x,int y)
{
    if(S[x].size()>=S[y].size()) std::swap(x,y);
    z.clear();
    for(it=S[x].begin();it!=S[x].end();++it)
    {
        int id=(*it).first;
        for(int j=0;j<H[id].size();++j)
        {
            ii=S[y].lower_bound(mp(H[id][j].second,0));
            if(ii==S[y].end()) continue;
            if((*ii).first==H[id][j].second) z.pb(mp(H[id][j],id));
        }
    }
    std::sort(z.begin(),z.end());
    for(int i=0;i<z.size();++i)
    {
        int _x=(z[i].first).second,_y=z[i].second,lefx,lefy;
        ii=S[y].lower_bound(mp(_x,0));
        jj=S[x].lower_bound(mp(_y,0));
        if(ii==S[y].end()||jj==S[x].end()||(*ii).first!=_x||(*jj).first!=_y)continue;
        ans+=2ll*min(lefx=(*ii).second,lefy=(*jj).second);
        S[y].erase(ii);S[x].erase(jj);
        if(lefx>lefy) S[y].insert(mp(_x,lefx-lefy));
        else S[x].insert(mp(_y,lefy-lefx));
    }
    for(it=S[x].begin();it!=S[x].end();++it)S[y].insert(*it);
    return y;
}
void dfs(int x)
{
    int n=G[x].size(),i;
    for(i=0;i<n;++i) dfs(G[x][i]);
    for(i=0;i<n;++i) lie[x]=Cb(lie[x],lie[G[x][i]]);
}
int main()
{
    N=read(),M=read(),K=read();
    int i,a,b;
    for(i=1;i<=N;++i) S[i].insert(mp(i,read())),lie[i]=i;
    for(i=1;i<=M;++i) a=read(),b=read(),G[b].pb(a),++c[a];
    for(i=1;i<=K;++i) a=read(),b=read(),H[a].pb(mp(i,b)),H[b].pb(mp(i,a));
    for(i=1;i<=N;++i) if(!c[i]) dfs(i);
    return 0*printf("%lld
",ans);
}

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