#include <bits/stdc++.h>
using namespace std;
const int MAXN = 3e5+1;
int cnt[MAXN+1];
#define pb push_back
#define sz(a) (int)(a.size())
typedef long long int ll;
typedef vector<vector<int>>vii;
vii adj(1111);
bool ok = 1,vis[1111];
void dfs(int v,int u){
vis[v] = 1;
for(int x:adj[v]){
if(x == u)continue;
if(vis[x])ok = 0;
else dfs(x,v);
}
}
int main()
{
//the graph must be a tree
//if have cycle then bob's possible space never decreases around the cycle
//how to solve when have tree?
//think about search space of bob
//each turn a on state becomes off and turn everything incident to it on
//alice can pick a node and off it
//can she make everything off?
int n,m;
cin>>n>>m;
for(int i=0;i<m;i++){
int v,u;
cin>>v>>u;
adj[v].pb(u);
adj[u].pb(v);
}
dfs(1,0);
if(ok)dfs2(1,0);
if(ok){
cout<<"YES"<<'\n';
cout<<2<<'\n';
cout<<1<<" "<<1;
}
else cout<<"NO";
}
Compilation message
newspapers.cpp: In function 'int main()':
newspapers.cpp:40:8: error: 'dfs2' was not declared in this scope; did you mean 'dfs'?
40 | if(ok)dfs2(1,0);
| ^~~~
| dfs
