Submission #364762

#	Time	Username	Problem	Language	Result	Execution time	Memory
364762		MohamedAhmed04	Sjekira (COCI20_sjekira)	C++14	110 / 110	93 ms	10856 KiB

sjekira

#include <bits/stdc++.h>

using namespace std ;

const int MAX = 1e5 + 10 ;

int arr[MAX] ;
int n ;

vector< vector<int> >adj(MAX) ;
vector< pair<int , int> >vp ;

int par[MAX] , sz[MAX] , val[MAX] ;
int mark[MAX] ;

void init()
{
	for(int i = 1 ; i <= n ; ++i)
		par[i] = i , sz[i] = 1 , val[i] = arr[i] ;
}

int root(int node)
{
	if(par[node] == node)
		return node ;
	return (par[node] = root(par[node])) ;
}

void Union(int x , int y)
{
	int a = root(x) ;
	int b = root(y) ;
	if(sz[a] < sz[b])
		swap(a , b) ;
	par[b] = a ;
	sz[a] += sz[b] ;
	val[a] = max(val[a] , val[b]) ;
}

int main()
{
	ios_base::sync_with_stdio(0) ;
	cin.tie(0) ;
	cin>>n ;
	for(int i = 1 ; i <= n ; ++i)
	{
		cin>>arr[i] ;
		vp.emplace_back(arr[i] , i) ;
	}
	for(int i = 0 ; i < n-1 ; ++i)
	{
		int x , y ;
		cin>>x>>y ;
		adj[x].push_back(y) ;
		adj[y].push_back(x) ;
	}
	init() ;
	sort(vp.begin() , vp.end()) ;
	long long ans = 0 ;
	for(auto &p : vp)
	{
		int node = p.second ;
		mark[node] = 1 ;
		for(auto &child : adj[node])
		{
			if(mark[child])
				ans += arr[node] + val[root(child)] ;
		}
		for(auto &child : adj[node])
		{
			if(mark[child])
				Union(node , child) ;
		}
	}
	return cout<<ans<<"\n" , 0 ;
}		

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