#include<bits/stdc++.h>
using namespace std;
#define LL long long
#define pii pair<int, int>
#define F first
#define S second
const int maxn =5e5+10;
const int mod=1e9+7;
int n, m;
int vis[maxn];
vector<pii> v[maxn];
int dfs(int x, int last){
if(x==1) return 1;
for(auto[y, id]: v[x]){
if(y==last) continue;
return dfs(y, x);
}
return 0;
}
int GetMove(){
int ret; cin>>ret;
return ret;
}
void MakeMove(int v){
cout << v << endl;
}
signed main(){
//ios_base::sync_with_stdio(0); cin.tie(0);
cin>>n>>m;
for(int i=0; i<m; i++){
int x, y; cin>>x>>y;
v[x].push_back( {y, i} );
v[y].push_back( {x, i} );
}
for(auto[y, id]: v[1]){
if( dfs(y, 1)==0 ){
cout << "NO" << endl;
return 0;
}
}
cout << "YES" << endl;
int cur=1, last=1;
while(true){
cur=GetMove();
last=1;
if(cur==0){ return 0; }
while(cur!=1){
for(auto[y, id]: v[cur]){
if(y!=last){
last=cur, cur=y;
break;
}
}
MakeMove(cur);
}
}
// cout << "NO" << endl;
return 0;
}
