Submission #778796

#	Time	Username	Problem	Language	Result	Execution time	Memory
778796		FEDIKUS	Newspapers (CEOI21_newspapers)	C++17	0 / 100	0 ms	212 KiB

newspapers

#include<bits/stdc++.h>

using namespace std;

const int maxn=1010;

vector<int> g[maxn];

pair<int,int> dfs(int node,int par=1,int parent=-1){
    pair<int,int> ret={0,0};
    for(int i:g[node]){
        if(i==parent) continue;
        auto temp=dfs(i,par^1,node);
        ret.first+=temp.first;
        ret.second+=temp.second;
    }
    if(par&1) ret.first++;
    else ret.second++;
    return ret;
}

int main(){
    int n,m;
    cin>>n>>m;
    for(int i=1;i<=m;i++){
        int u,v;
        cin>>u>>v;
        g[u].push_back(v);
        g[v].push_back(u);
    }
    if(m!=n-1){
        cout<<"NO\n";
        return 0;
    }
    auto res=dfs(1);
    if(res.first>2 && res.second>2){
        cout<<"NO\n";
        return 0;
    }else cout<<"YES\n0";
    return 0;
}
/*
7 6
1 2
1 3
1 4
1 5
1 6
1 7

6 6
1 2
2 3
3 1
1 4
2 5
3 6
*/

• Subtask 1: 0 / 12
• Subtask 2: 0 / 8
• Subtask 3: 0 / 80