Submission #810965

#	Time	Username	Problem	Language	Result	Execution time	Memory
810965		owoovo	Stranded Far From Home (BOI22_island)	C++17	15 / 100	1060 ms	524288 KiB

island

#include<bits/stdc++.h>
#define ll long long
using namespace std;
ll n,m,val[200010],tag[200010],subsum[200010],dsu[200010],ans[200010];
vector<ll> e[200010],te[200010];
priority_queue<pair<int,int>,vector<pair<int,int>>,greater<pair<int,int>>> pq;
int f(int now){
    if(dsu[now]!=now) dsu[now]=f(dsu[now]);
    return dsu[now];
}
void onion(int a,int b){
    a=f(a);
    b=f(b);
    if(a!=b) dsu[b]=a,subsum[a]+=subsum[b];
    return;
}
void dfs(int now,int x){
    ans[now]=x;
    if(tag[now]==1)ans[now]=0;
    for(auto ne:te[now]){
        dfs(ne,ans[now]);
    }
}
int main(){
    ios::sync_with_stdio(0);
    cin.tie(0);
    cin>>n>>m;
    int last=1;
    for(int i=1;i<=n;i++){
        cin>>val[i];
        pq.push(make_pair(val[i],i));
        dsu[i]=i;
        subsum[i]=val[i];
    }
    for(int i=0;i<m;i++){
        int a,b;
        cin>>a>>b;  
        if(val[a]>val[b])e[a].push_back(b);
        else e[b].push_back(a);
    }
    while(!pq.empty()){
        auto x=pq.top();
        pq.pop();
        last=x.second;
        for(auto ne:e[x.second]){
            ne=f(ne);
            if(ne==x.second)continue;
            te[x.second].push_back(ne);
            if(subsum[ne]<x.first)tag[ne]=1;
            onion(x.second,ne);
        }
    }
    dfs(last,1);
    for(int i=1;i<=n;i++)cout<<ans[i];
    cout<<"\n";
    return 0;
}

• Subtask 1: 0 / 10
• Subtask 2: 0 / 10
• Subtask 3: 15 / 15
• Subtask 4: 0 / 30
• Subtask 5: 0 / 35