#include<iostream>
#include<cstdio>
#include<algorithm>
#include<cstring>
#include<set>
#include<vector>
#include<queue>
using namespace std;
const int MAXN=3001;
int n,p,a[MAXN],b[MAXN],c,x,y,z,hh=1,hhh,sum=0;
int main()
{
	freopen("salenet.in","r",stdin);
	freopen("salenet.out","w",stdout);
	scanf("%d%d",&n,&p);
	memset(a,0,sizeof(a));
	for(int i=1;i<=p;i++)
	{
		scanf("%d%d",&z,&b[i]);
		a[z]=1;sum+=b[i];
	}
	scanf("%d",&c);
	for(int i=1;i<=c;i++)
	{
		scanf("%d%d",&x,&y);
		if(a[x])a[y]=1;
	}
	for(int i=1;i<=n;i++)
	if(!a[i])
	{
		hh=0;hhh=i;
		break;
	}
	if(!hh)
	cout<<"NO"<<hhh;
	else cout<<"YES"<<sum;
	return 0;
}