#include<bits/stdc++.h>
using namespace std;

int main(){
  int n,m;
  cin>>n>>m;
  vector<vector<int>> g(n);
  for (int i=0;i<m;i++){
    int u,v;
    cin>>u>>v;
    u--;v--;
    g[u].push_back(v);
    g[v].push_back(u);
  }
  int l;
  cin>>l;
  vector<int> dist(n,-1);
  priority_queue<pair<int,int>> q;
  for (int i=0;i<l;i++){
    int j,k;
    cin>>j>>k;
    j--;
    q.push({k,j});
  }
  while (!q.empty()){
    auto [d,v]=q.top();
    q.pop();
    if (dist[v]!=-1) continue;
    dist[v]=d;
    if (dist[v]==0) continue;
    for (int u:g[v]){
      q.push({dist[v]-1,u});
    }
  }
  vector<int> dist2(n,-1);
  queue<int> q2;
  if (dist[0]==-1){
    dist2[0]=0;
    q2.push(0);
  }
  while (!q2.empty()){
    int v=q2.front();
    q2.pop();
    for (int u:g[v]){
      if (dist[u]!=-1) continue;
      if (dist2[u]!=-1) continue;
      dist2[u]=dist2[v]+1;
      q2.push(u);
    }
  }
  if (dist2[n-1]>=0){
    cout<<"Yes\n";
    cout<<dist2[n-1]<<endl;
  }
  else cout<<"No\n";
}