Submission #863837

#	Time	Username	Problem	Language	Result	Execution time	Memory
863837		vjudge1	Sjekira (COCI20_sjekira)	C++17	110 / 110	41 ms	13456 KiB

sjekira

#include<bits/stdc++.h>
#define fi first
#define se second
using namespace std;
using ll=long long;
int n;
pair<int,int> w[100005];
vector<int>v[100005];
bool cmp(pair<int,int>a,pair<int,int>b)
{
    return a.fi<b.fi;
}
int pa[100005],ma[100005],sz[1000005];
int findd(int u)
{
    if(pa[u]!=u) pa[u]=findd(pa[u]);
    return pa[u];
}
ll ans=0;
void uni(int a,int b)
{
    a=findd(a);b=findd(b);
    //cout<<a<<" "<<b<<endl;
    if(a!=b)
    {
        if(sz[a]>sz[b]) swap(a,b);
        pa[a]=b;
        sz[b]+=sz[a];
        ans=(ans+ma[a]+ma[b]);
        ma[b]=max(ma[b],ma[a]);
    }
}
bool t[100005];
int main()
{
    cin.tie(0)->sync_with_stdio(0);
    //freopen(".inp","r",stdin);
    //freopen(".out","w",stdout);
    cin>>n;
    for(int i=1;i<=n;i++) cin>>w[i].fi;
    for(int i=1;i<=n;i++) w[i].se=i;
    for(int i=1;i<n;i++)
    {
        int x,y;cin>>x>>y;
        v[x].push_back(y);
        v[y].push_back(x);
    }
    for(int i=1;i<=n;i++) ma[i]=w[i].fi;
    sort(w+1,w+n+1,cmp);
    for(int i=1;i<=n;i++) pa[i]=i,sz[i]=1;
    t[w[1].se]=true;
    for(int i=2;i<=n;i++)
        {
            for(int j:v[w[i].se]) if(t[j]) uni(w[i].se,j);
            t[w[i].se]=true;
        }
    cout<<ans;
    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 30 / 30
• Subtask 4: 60 / 60