#include <bits/stdc++.h>
#include <chrono>
#define ll long long int
#define endl '\n'
#define vn vector<ll>
#define vi vector<pair <ll,ll>>
using namespace std;
using namespace std::chrono;
const int MAX_N = 1e9 + 7;
#define pii pair<ll,ll>
const ll INF = 0x3f3f3f3f3f3f3f3f;
#define pb push_back
#define srt(vp) sort(vp.begin(), vp.end())
int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
auto start = high_resolution_clock::now();
ll n,m;
cin>>n>>m;
vector <vn> adj(n+m+1);
vector <bool> check(n+m+1,false);
for (int i=0;i<n+m-1;i++){
ll a,b;
cin>>a>>b;
if (a <= n)check[b]=true;
if (b <= n)check[a]=true;
adj[a].pb(b);
adj[b].pb(a);
}
for (int i=1;i<=n-1;i++){
cout<<i<<" "<<1<<endl;
}
auto stop = high_resolution_clock::now();
auto duration = duration_cast<microseconds>(stop - start);
//cout << "Time taken by function: " << duration.count() << " microseconds" << endl;
return 0;
}
