제출 #1159341

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1159341		Kaztaev_Alisher	Spring cleaning (CEOI20_cleaning)	C++20	0 / 100	1095 ms	18624 KiB

cleaning

#include <bits/stdc++.h>

#define ios ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define file(s) if (fopen(s".in", "r")) freopen(s".in", "r", stdin), freopen(s".out", "w", stdout)
#define all(a) a.begin() , a.end()
#define F first
#define S second

using namespace std;
using ll = long long;

const ll N = 2e5+5 , inf = 2e9 + 7;
const ll INF = 1e18 ,   mod = 1e9+7;

ll a[N] , b[N] , mx , mx2 , par[N] , was[N]  , dp[N];
vector<int> g[N] , vec;
map<pair<int,int> ,int> mp;
void dfs(int v, int p){
	par[v] = p;
	// cout << v <<" " << dp[v] << "\n";
	if(mx != v && dp[v] > dp[mx2] && was[v] == 0 && g[v].size() == 1) mx2 = v;
	for(int to : g[v]){
		if(to != p){
			if(mp[{v,to}] == 1){
				dp[to] = dp[v]-1;
			} else {
				dp[to] = dp[v]+1;
			}
			dfs(to,v);
		}
	}
}

void solve(){
	int n , q;
	cin >> n >> q;
	for(int i = 1; i < n; i++){
		cin >> a[i] >> b[i];
	}
	while(q--){
		int k;
		cin >> k;
		for(int i = 1; i <= n+k; i++) g[i].clear() , was[i] = par[i] = 0;
		for(int i = 1; i < n; i++){
			g[a[i]].push_back(b[i]);
			g[b[i]].push_back(a[i]);
		}
		for(int i = 1; i <= k; i++){
			int a;
			cin >> a;
			g[a].push_back(i+n);
			g[i+n].push_back(a);
		}
		int res = 0;
		for(int i = 1; i <= n+k; i++){
			if(g[i].size() == 1) res++;
		}
		// cout << res << "\n";
		// return;
		if(res % 2){
			cout << "-1\n";
			continue;;
		}
		// return;
		int ans = 0 , cnt = 0;
		mp.clear();
		// int k1 = 4;
		dp[n+k+1] = -inf;
		while(1){
			for(int i = 1; i <= n+k; i++) dp[i] = 0;
			for(int i = 1; i <= n+k; i++){
				if(g[i].size() == 1 && was[i] == 0){
					mx = i;
					break;
				}
			}
			mx2 = n+k+1;
			dp[mx] = 0;
			dfs(mx,0);
	
	
			mx = mx2;
			mx2 = n+k+1;
			
			dp[mx] = 0;
			dfs(mx,0);
			
			// cout << mx <<" " << mx2 <<"\n";
			
			mx = mx2;
			
			vector<int> path;
			while(mx > 0){
				path.push_back(mx);
				mx = par[mx];
			}
			// cout << path[0] <<" " << path.back() <<"\n";
			for(int i = 0; i + 1 < path.size(); i++){
				if(mp[{path[i] , path[i+1]}] == 0){
					cnt++;
				}
				mp[{path[i],path[i+1]}] = 1;
				mp[{path[i+1],path[i]}] = 1;
			}
			was[path.back()] = was[path[0]] = 1;
			ans += path.size()-1;
			if(cnt == n+k-1) break;
		}
		cout << ans << "\n"; 
	}
}
/*

*/
signed main(){
	ios;
	solve();
}

• Subtask 1: 0 / 0
• Subtask 2: 0 / 9
• Subtask 3: 0 / 9
• Subtask 4: 0 / 16
• Subtask 5: 0 / 19
• Subtask 6: 0 / 17
• Subtask 7: 0 / 30