#include <bits/stdc++.h>
using namespace std;
const int N = 300005;
int n, m, k;
vector<int> g[N]; // adjacency (allowed edges)
vector<int> forbid[N]; // forbidden outgoing edges
bool vis[N];
int parent_[N];
bool is_forbidden(int u, int v) {
for (int x : forbid[u]) {
if (x == v) return true;
}
return false;
}
int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
cin >> n >> m >> k;
// m edges (if present in statement, ignored here if irrelevant to final structure)
for (int i = 0; i < m; i++) {
int a, b;
cin >> a >> b;
}
// forbidden edges
for (int i = 0; i < k; i++) {
int a, b;
cin >> a >> b;
forbid[a].push_back(b);
}
queue<int> q;
q.push(0);
vis[0] = true;
parent_[0] = -1;
while (!q.empty()) {
int u = q.front();
q.pop();
for (int v = 0; v < n; v++) {
if (vis[v]) continue;
if (is_forbidden(u, v)) continue;
vis[v] = true;
parent_[v] = u;
q.push(v);
}
}
for (int i = 0; i < n; i++) {
if (!vis[i]) {
cout << "NO\n";
return 0;
}
}
cout << "YES\n";
for (int i = 1; i < n; i++) {
cout << parent_[i] << " " << i << "\n";
}
return 0;
}
