Submission #1160277

#	Time	Username	Problem	Language	Result	Execution time	Memory
1160277		Kaztaev_Alisher	Spring cleaning (CEOI20_cleaning)	C++20	28 / 100	1096 ms	21064 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] , sz[N] , par[N] , cnt[N];
vector<int> g[N];
int ans = 0;
void go(int v , int p){
	par[v] = p;
	sz[v] = 0;
	for(int to : g[v]){
		if(to != p){
			go(to,v);
			sz[v] += sz[to];
		}
	}
	if(g[v].size() == 1) sz[v] = 1;
	if(sz[v] % 2 == 0) ans++;
}
void add(int x , int kol , int p){
	while(x > 0){
		if(sz[x] % 2 == 0) ans--;
		sz[x] += kol;
		if(sz[x] % 2 == 0) ans++;
		x = par[x];
	}
}
void solve(){
	int n , q;
	cin >> n >> q;
	for(int i = 1; i < n; i++){
		cin >> a[i] >> b[i];
		g[a[i]].push_back(b[i]);
		g[b[i]].push_back(a[i]);
	}
	int bas = 1;
	for(int i = 1; i <= n; i++){
		if(g[i].size() != 1){
			bas = i;
			break;
		}
	}
	go(bas,0);
	while(q--){
		int k;
		cin >> k;
		set<int> st;
		for(int i = 1; i <= k; i++){
			int a;
			cin >> a;
			cnt[a]++;
			st.insert(a);
		}
		for(auto x : st){
			add(x,cnt[x]-(g[x].size() == 1),0);
		}
		if(sz[bas] % 2 == 1) cout << "-1\n";
		else cout << ans+n+k-2 << "\n"; 
		for(auto x : st){
			add(x,-(cnt[x]-(g[x].size() == 1)),0);
			cnt[x] = 0;
		}
	}
}
/*

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

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