#include <bits/stdc++.h>
//#include <atcoder/all>
using namespace std;
//using namespace atcoder;
//using mint = modint1000000007;
//const int mod = 1000000007;
//using mint = modint998244353;
//const int mod = 998244353;
const int INF = 1e9;
//const long long LINF = 1e18;
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep2(i,l,r)for(int i=(l);i<(r);++i)
#define rrep(i, n) for (int i = (n) - 1; i >= 0; --i)
#define rrep2(i,l,r)for(int i=(r) - 1;i>=(l);--i)
#define all(x) (x).begin(),(x).end()
#define allR(x) (x).rbegin(),(x).rend()
#define P pair<int,int>
template<typename A, typename B> inline bool chmax(A & a, const B & b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A & a, const B & b) { if (a > b) { a = b; return true; } return false; }

int main() {
	std::ios::sync_with_stdio(false);
	std::cin.tie(nullptr);
	int n, m; cin >> n >> m;
	vector to(n, vector<int>());
	rep(i, m) {
		int u, v; cin >> u >> v;
		u--, v--;
		to[u].push_back(v);
		to[v].push_back(u);
	}
	vector<int> dp(n, -1);
	{
		priority_queue<P>pq;// queでいいわ
		int l; cin >> l;
		rep(i, l) {
			int j, k; cin >> j >> k;
			j--;
			if (chmax(dp[j], k))pq.emplace(k, j);
		}
		while (!pq.empty()) {
			auto[d, v] = pq.top();
			pq.pop();
			if (d == 0)continue;
			if (dp[v] > d)continue;
			for (auto nv : to[v]) {
				if (chmax(dp[nv], d - 1)) {
					pq.emplace(d - 1, nv);
				}
			}
		}
	}
	vector<int>dp2(n, INF);
	queue<int>que;
	if (dp[0] == -1) {
		que.push(0);
		dp2[0] = 0;
	}
	while (!que.empty()) {
		auto v = que.front();
		que.pop();
		for (auto nv : to[v]) {
			if (dp[nv] != -1)continue;
			if (chmin(dp2[nv], dp2[v] + 1)) {
				que.push(nv);
			}
		}
	}
	if (dp2[n - 1] != INF) {
		cout << "Yes" << endl;
		cout << dp2[n - 1] << endl;
	}
	else {
		cout << "No" << endl;
	}
	//rep(i, n)cout << i << " " << dp[i] << endl;
	return 0;
}