Submission #975115

#	Time	Username	Problem	Language	Result	Execution time	Memory
975115		8pete8	Security Guard (JOI23_guard)	C++17	37 / 100	282 ms	25272 KiB

guard

#include<iostream>
#include<stack>
#include<map>
#include<vector>
#include<string>
#include<unordered_map>
#include <queue>
#include<cstring>
#include<limits.h>
#include <cassert>
#include<cmath>
#include<set>
#include<algorithm>
#include <iomanip>
#include<numeric> //gcd(a,b)
#include<bitset>
#include <cstdlib> 
#include <cstdint>
using namespace std;
#define ll long long
#define f first
//#define endl "\n"
#define s second
#define pii pair<int,int>
#define ppii pair<int,pii>
#define vi vector<int>
#define pb push_back
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define F(n) for(int i=0;i<n;i++)
#define lb lower_bound
#define ub upper_bound
#define fastio ios::sync_with_stdio(false);cin.tie(NULL);
#pragma GCC optimize ("03,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
using namespace std;
#define int long long
#define double long double
const int mxn=2e5,inf=1e18,minf=-1e18;
int val[mxn+10];
vector<int>adj[mxn+10];
int mark[mxn+10];
int32_t main(){
	int n,m,q;cin>>n>>m>>q;
	if(q)return 0;
	for(int i=1;i<=n;i++)cin>>val[i];
	for(int i=0;i<n-1;i++){
		int a,b;cin>>a>>b;
		adj[a].pb(b);
		adj[b].pb(a);
	}
	pair<pii,int> st={{minf,0},-1};
	for(int i=1;i<=n;i++)st=max(st,{{val[i],adj[i].size()},i});
	int ans=0;
	priority_queue<pair<pii,int>,vector<pair<pii,int>>,greater<pair<pii,int>>>pq;
	//greedy cost, if cost equal then we take the node with the least val first(wanna keep the large val as leaf)
	pq.push({{0,0},st.s});
	while(!pq.empty()){
		int cur=pq.top().s,cost=pq.top().f.f;
		pq.pop();
		if(mark[cur])continue;
		mark[cur]=1;
		ans+=cost;
		for(auto i:adj[cur])pq.push({{val[cur],val[i]},i});
	}
	cout<<ans;
	return 0;
}
/*
non tree
we still need to take the max
we still need to have everything connected

we can find mst? cost->val of node????
*/

• Subtask 1: 12 / 12
• Subtask 2: 13 / 13
• Subtask 3: 12 / 12
• Subtask 4: 0 / 13
• Subtask 5: 0 / 8
• Subtask 6: 0 / 18
• Subtask 7: 0 / 24