#include <bits/stdc++.h>
using namespace std;
const int MAXN = 3e5 + 10;
int deg[MAXN];
vector<int> adj[MAXN];
set<int> p[MAXN], not_visited;
vector<pair<int, int>> edges;
bool dfs(int v, bool ans){
bool ret = true;
for(auto u : adj[v]){
if(!not_visited.count(u)) return false;
not_visited.erase(u);
ret &= dfs(u, ans);
if(ans) edges.push_back({u, v});
}
vector<int> to_visit;
for(auto u : not_visited) if(!deg[u] && !p[v].count(u)) to_visit.push_back(u);
for(auto u : to_visit) not_visited.erase(u);
for(auto u : to_visit){
ret &= dfs(u, ans);
if(ans) edges.push_back({u, v});
}
return ret;
}
int main(){
cin.tie(0)->sync_with_stdio(0);
int n, m, k; cin >> n >> m >> k;
while(m--){
int a, b; cin >> a >> b;
adj[b].push_back(a);
deg[a] ++;
}
while(k--){
int a, b; cin >> a >> b;
p[b].insert(a);
}
for(int i=0; i<n; i++){
if(deg[i] > 1){
cout << "NO\n";
return 0;
}
}
for(int i=0; i<n; i++) not_visited.insert(i);
int root = -1;
for(int i=0; i<n; i++){
if(not_visited.count(i)){
not_visited.erase(i);
dfs(i, 0);
root = i;
}
}
for(int i=0; i<n; i++) if(i != root) not_visited.insert(i);
if(!dfs(root, 1) || !not_visited.empty()){
cout << "NO\n";
return 0;
}
for(auto [a, b] : edges) cout << a << " " << b << "\n";
return 0;
}
