Submission #810974

#	Time	Username	Problem	Language	Result	Execution time	Memory
810974		owoovo	Stranded Far From Home (BOI22_island)	C++17	15 / 100	335 ms	524288 KiB

island

#include<bits/stdc++.h>
#define ll long long
using namespace std;
ll n,m,tag[200010],subsum[200010],dsu[200010],ans[200010];
vector<ll> e[200010],te[200010];
pair<ll,ll> val[200010];
int f(int now){
    if(dsu[now]!=now) dsu[now]=f(dsu[now]);
    return dsu[now];
}
void dfs(int now,int x){
    tag[now]==1?ans[now]=0:ans[now]=x;
    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].first;
        val[i].second=i;
        dsu[i]=i;
        subsum[i]=val[i].first;
    }
    for(int i=0;i<m;i++){
        int a,b;
        cin>>a>>b;  
        if(val[a].first>val[b].first)e[a].push_back(b);
        else e[b].push_back(a);
    }
    sort(&val[1],&val[n+1]);
    for(int i=1;i<=n;i++){
        ll x=val[i].second;
        ll y=val[i].first;
        for(auto ne:e[x]){
            ne=f(ne);
            if(ne==x)continue;
            te[x].push_back(ne);
            if(subsum[ne]<y)tag[ne]=1;
            dsu[ne]=x;
            subsum[x]+=subsum[ne];
        }
    }
    dfs(val[n].second,1);
    for(int i=1;i<=n;i++)cout<<ans[i];
    cout<<"\n";
    return 0;
}

Compilation message (stderr)

island.cpp: In function 'int main()':
island.cpp:21:9: warning: unused variable 'last' [-Wunused-variable]
   21 |     int last=1;
      |         ^~~~

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