Submission #1244870

#	Time	Username	Problem	Language	Result	Execution time	Memory
1244870		mountainsalt	Spring cleaning (CEOI20_cleaning)	C++20	9 / 100	43 ms	9912 KiB

cleaning

#include <bits/stdc++.h>
#define int long long

using namespace std;

const int mod=1e9+7;
const int N=1e5+5;

int n, q, deg[N];
vector<int> adj[N];

signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cin >> n >> q;
    for(int i=1; i<n; i++){
        int u, v;
        cin >> u >> v;
        adj[u].emplace_back(v);
        adj[v].emplace_back(u);
        deg[u]++;
        deg[v]++;
    }
    int __=1;
    while(__++<=q){
        int m; 
        cin >> m;
        unordered_map<int,int> freq;
        int add=0,dist=0;
        for(int i=1; i<=m; i++){
            int v;
            cin >> v;
            dist+=(freq.find(v)==freq.end());
            freq[v]++;
            if(freq[v]%2==0) add++;
            else if(freq[v]>1) add--;
        }
        if((n-1-dist+m)%2==0) cout << n-1+m+add << "\n";
        else cout << "-1\n";
    }
}

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