#include<stdio.h>
int u[400005], v[400005];
int r[200005];
int h[400005], l, z;
int comp_h(int a, int b)
{
	if (z == 0)
	{
		if (u[h[a]] > u[h[b]])
			return 1;
		else
			return -1;
	}
	else
	{
		if (r[h[a]] < r[h[b]])
			return 1;
		else
			return -1;
	}
}
void swap_h(int a, int b)
{
	int f = h[a];
	h[a] = h[b];
	h[b] = f;
	return;
}
void push(int ne)
{
	h[l] = ne;
	int p = l++;
	for (; p > 0; p = (p - 1) / 2)
		if (comp_h((p - 1) / 2, p) > 0)
			swap_h((p - 1) / 2, p);
	return;
}
int pop()
{
	swap_h(0, --l);
	int p = 0;
	for (;;)
	{
		if (2 * p + 2 < l)
		{
			if (comp_h(2 * p + 1, 2 * p + 2) > 0)
			{
				if (comp_h(p, 2 * p + 2) > 0)
					swap_h(p, 2 * p + 2);
				p = 2 * p + 2;
			}
			else
			{
				if (comp_h(p, 2 * p + 1) > 0)
					swap_h(p, 2 * p + 1);
				p = 2 * p + 1;
			}
		}
		else if (2 * p + 1 < l)
		{
			if (comp_h(p, 2 * p + 1) > 0)
				swap_h(p, 2 * p + 1);
			p = 2 * p + 1;
		}
		else
			break;
	}
	return h[l];
}
int id[400005];
int dist[200005];
int q[200005], left, right;
int main()
{
	int n, m;
	scanf("%d %d", &n, &m);
	int i;
	for (i = 0; i < m; i++)
	{
		scanf("%d %d", &u[i], &v[i]);
		u[i + m] = --v[i];
		v[i + m] = --u[i];
	}
	m *= 2;
	z = 0;
	l = 0;
	for (i = 0; i < m; i++)
		push(i);
	for (i = 0; i < m; i++)
		id[i] = pop();
	id[m] = m;
	u[m] = -1;
	int j, k;
	for (i = 0; i < n; i++)
		r[i] = -1;
	scanf("%d", &l);
	for (i = 0; i < l; i++)
	{
		scanf("%d %d", &j, &k);
		if (r[--j] < k)
			r[j] = k;
	}
	z = 1;
	l = 0;
	for (i = 0; i < n; i++)
		if (r[i] > 0)
			push(i);
	int min, mid, max;
	while (l > 0)
	{
		i = pop();
		min = -1;
		max = m;
		while (max - min > 1)
		{
			mid = (max + min) / 2;
			if (u[id[mid]] < i)
				min = mid;
			else
				max = mid;
		}
		for (; u[id[max]] == i; max++)
		{
			if (r[v[id[max]]] < r[i] - 1)
			{
				r[v[id[max]]] = r[i] - 1;
				push(v[id[max]]);
			}
		}
	}
	for (i = 0; i < n; i++)
		dist[i] = 1e9;
	left = right = 0;
	if (r[0] < 0)
	{
		dist[0] = 0;
		q[right++] = 0;
	}
	while (left < right)
	{
		i = q[left++];
		min = -1;
		max = m;
		while (max - min > 1)
		{
			mid = (max + min) / 2;
			if (u[id[mid]] < i)
				min = mid;
			else
				max = mid;
		}
		for (; u[id[max]] == i; max++)
		{
			if (dist[v[id[max]]] > dist[i] + 1 && r[v[id[max]]] < 0)
			{
				dist[v[id[max]]] = dist[i] + 1;
				q[right++] = v[id[max]];
			}
		}
	}
	if (dist[n - 1] > 1e8)
		printf("No\n");
	else
		printf("Yes\n%d\n", dist[n - 1]);
	return 0;
}