#include<bits/stdc++.h>
using namespace std;
#define int long long
#define pb push_back
#define myPair pair<int,int>
#define mp make_pair
#define fi first
#define se second
#define qmax priority_queue<int>
#define qmin priority_queue<int,vector<int>,greater<int>>
#define all(x) x.begin(),x.end()
#define FOR(i,a,b) for(int i = a; i <= b; i++)
#define FORR(i,a,b) for(int i = a; i >= b; i--)
const int mxn = 1e6 + 10;
vector<int> g[mxn];
int n, r, m; // number of vertices, edges and soldiers respectively
int color[mxn];
vector<pair<int,int>> sol;
bool flag;
void dfs(int u, int par, int level, int k)
{
if(level == k + 1)
return;
color[u] = 1;
for(int v : g[u]) {
if(v == par)
continue;
if(!color[v])
dfs(v, u, level + 1, k);
else if(color[v] && level != k)
flag = 0;
}
}
void solve()
{
cin >> n >> r >> m;
FOR(i, 1, n) {
g[i].clear();
}
sol.clear();
FOR(i, 1, r) {
int u, v; cin >> u >> v;
g[u].pb(v);
g[v].pb(u);
}
FOR(i, 1, m) {
int a, b; cin >> a >> b;
sol.pb(mp(a, b)); // city number and soldier's strength
}
memset(color, 0, sizeof(color));
flag = 1;
for(auto it : sol)
{
int city = it.fi;
if(!color[city])
dfs(city, -1, 0, it.se);
else if(color[city]) {
flag = 0;
break;
}
}
FOR(i, 1, n) {
if(!color[i]) {
flag = 0;
break;
}
}
if(flag)
cout << "Yes\n";
else
cout << "No\n";
}
int32_t main()
{
#ifndef ONLINE_JUDGE
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#endif
ios_base::sync_with_stdio(false);
cin.tie(NULL);
int t;
cin>>t;
while(t--)
solve();
return 0;
}
I2luY2x1ZGU8Yml0cy9zdGRjKysuaD4KdXNpbmcgbmFtZXNwYWNlIHN0ZDsKI2RlZmluZSBpbnQgbG9uZyBsb25nCiNkZWZpbmUgcGIgcHVzaF9iYWNrCiNkZWZpbmUgbXlQYWlyIHBhaXI8aW50LGludD4KI2RlZmluZSBtcCBtYWtlX3BhaXIKI2RlZmluZSBmaSBmaXJzdAojZGVmaW5lIHNlIHNlY29uZAojZGVmaW5lIHFtYXggcHJpb3JpdHlfcXVldWU8aW50PgojZGVmaW5lIHFtaW4gcHJpb3JpdHlfcXVldWU8aW50LHZlY3RvcjxpbnQ+LGdyZWF0ZXI8aW50Pj4KI2RlZmluZSBhbGwoeCkgeC5iZWdpbigpLHguZW5kKCkKI2RlZmluZSBGT1IoaSxhLGIpIGZvcihpbnQgaSA9IGE7IGkgPD0gYjsgaSsrKQojZGVmaW5lIEZPUlIoaSxhLGIpIGZvcihpbnQgaSA9IGE7IGkgPj0gYjsgaS0tKQoKY29uc3QgaW50IG14biA9IDFlNiArIDEwOwp2ZWN0b3I8aW50PiBnW214bl07CmludCBuLCByLCBtOwkvLyBudW1iZXIgb2YgdmVydGljZXMsIGVkZ2VzIGFuZCBzb2xkaWVycyByZXNwZWN0aXZlbHkKaW50IGNvbG9yW214bl07CnZlY3RvcjxwYWlyPGludCxpbnQ+PiBzb2w7CmJvb2wgZmxhZzsKCnZvaWQgZGZzKGludCB1LCBpbnQgcGFyLCBpbnQgbGV2ZWwsIGludCBrKQp7CglpZihsZXZlbCA9PSBrICsgMSkKCQlyZXR1cm47CgoJY29sb3JbdV0gPSAxOwoJZm9yKGludCB2IDogZ1t1XSkgewoJCWlmKHYgPT0gcGFyKQoJCQljb250aW51ZTsKCQlpZighY29sb3Jbdl0pCgkJCWRmcyh2LCB1LCBsZXZlbCArIDEsIGspOwoJCWVsc2UgaWYoY29sb3Jbdl0gJiYgbGV2ZWwgIT0gaykKCQkJZmxhZyA9IDA7Cgl9Cn0KCnZvaWQgc29sdmUoKQp7CgljaW4gPj4gbiA+PiByID4+IG07CglGT1IoaSwgMSwgbikgewoJCWdbaV0uY2xlYXIoKTsKCX0KCXNvbC5jbGVhcigpOwoJRk9SKGksIDEsIHIpIHsKCQlpbnQgdSwgdjsJY2luID4+IHUgPj4gdjsKCQlnW3VdLnBiKHYpOwoJCWdbdl0ucGIodSk7Cgl9CglGT1IoaSwgMSwgbSkgewoJCWludCBhLCBiOwljaW4gPj4gYSA+PiBiOwoJCXNvbC5wYihtcChhLCBiKSk7CS8vIGNpdHkgbnVtYmVyIGFuZCBzb2xkaWVyJ3Mgc3RyZW5ndGgKCX0KCW1lbXNldChjb2xvciwgMCwgc2l6ZW9mKGNvbG9yKSk7CgoJZmxhZyA9IDE7Cglmb3IoYXV0byBpdCA6IHNvbCkKCXsKCQlpbnQgY2l0eSA9IGl0LmZpOwoJCWlmKCFjb2xvcltjaXR5XSkKCQkJZGZzKGNpdHksIC0xLCAwLCBpdC5zZSk7CgkJZWxzZSBpZihjb2xvcltjaXR5XSkgewoJCQlmbGFnID0gMDsKCQkJYnJlYWs7CgkJfQoJfQoJCglGT1IoaSwgMSwgbikgewoJCWlmKCFjb2xvcltpXSkgewoJCQlmbGFnID0gMDsKCQkJYnJlYWs7CgkJfQoJfQoKCWlmKGZsYWcpCgkJY291dCA8PCAiWWVzXG4iOwoJZWxzZQoJCWNvdXQgPDwgIk5vXG4iOwp9CgppbnQzMl90IG1haW4oKQp7CiNpZm5kZWYgT05MSU5FX0pVREdFCglmcmVvcGVuKCJpbnB1dC50eHQiLCAiciIsIHN0ZGluKTsKCWZyZW9wZW4oIm91dHB1dC50eHQiLCAidyIsIHN0ZG91dCk7CiNlbmRpZgoKCWlvc19iYXNlOjpzeW5jX3dpdGhfc3RkaW8oZmFsc2UpOwoJY2luLnRpZShOVUxMKTsKCglpbnQgdDsKCWNpbj4+dDsKCXdoaWxlKHQtLSkKCQlzb2x2ZSgpOwoJCglyZXR1cm4gMDsKfQ==