Submission #1102192

#	Time	Username	Problem	Language	Result	Execution time	Memory
1102192		quocthang	Sjekira (COCI20_sjekira)	C++14	110 / 110	48 ms	7636 KiB

sjekira

#include <bits/stdc++.h>
#define base 31
#define fi first
#define endl "\n"
#define se second
#define NAME "FILE"
#define ll long long
#define int long long
#define mod 1000000007
#define pii pair<int,int>
#define bit(mask,i) (mask&(1<<i))
#define lcm(a,b) ((a*b)/__gcd(a,b))
#define turn_on(mask,i) (mask|(1<<i))
#define turn_off(mask,i) (mask^(1<<i))

template <class T1, class T2>
bool maximize(T1 &a, T2 b){if (a < b){a = b; return 1;} return 0;}

template <class T1, class T2>
bool minimize(T1 &a, T2 b){if (a > b){a = b; return 1;} return 0;}

template <class T1, class T2>
void add(T1 &a, T2 b){a += b; if (a >= mod) a -= mod;}

template <class T1, class T2>
void sub(T1 &a, T2 b){a -= b; if (a < 0) a += mod;}

using namespace std;
int sz[100010],mx[100010],res;
int find(int u){ return sz[u]<0?u:sz[u]=find(sz[u]);}
void Union(int u,int v){
	u=find(u);v=find(v);
	if(u==v)return ;
	res+=mx[u]+mx[v];
	if(sz[u]>sz[v])swap(u,v);
	sz[u]+=sz[v];
	sz[v]=u;
	maximize(mx[u],mx[v]);
}
int n;
vector<pair<int,pii>>q;
signed main(){
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);cout.tie(NULL);
	if (fopen(NAME".inp","r")){
		freopen(NAME".inp","r",stdin);
		freopen(NAME".out","w",stdout);
	}
	memset(sz,-1,sizeof sz);
	cin>>n;
	for(int i=1;i<=n;i++)cin>>mx[i];
	for(int i=1,u,v;i<n;i++){
		cin>>u>>v;
		q.push_back({max(mx[u],mx[v]),{u,v}});
	}
	sort(q.begin(),q.end());
	for(auto x:q){
		int u=x.se.fi,v=x.se.se;
		Union(u,v);
	}
	cout<<res;
}

Compilation message (stderr)

sjekira.cpp: In function 'int main()':
sjekira.cpp:46:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   46 |   freopen(NAME".inp","r",stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
sjekira.cpp:47:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   47 |   freopen(NAME".out","w",stdout);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

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