#include<stdio.h>
int u[200005], v[200005];
int h[200005], l;
int comp_h(int a, int b)
{
	if (u[h[a]] > u[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[200005];
int a[100005];
int val[100005];
int q[500005], left, right;
int dist[100005][5];
int main()
{
	int n, m;
	scanf("%d %d", &n, &m);
	int i, j;
	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;
	int k;
	scanf("%d", &k);
	for (i = 0; i < k; i++)
		scanf("%d", &a[i]);
	for (i = 0; i < n; i++)
		val[i] = 0;
	for (i = 0; i < k; i++)
		val[--a[i]]++;
	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 min, mid, max;
	for (i = 0; i < n; i++)
		for (j = 0; j < 5; j++)
			dist[i][j] = 1e9;
	dist[0][0] = 0;
	q[0] = 0;
	left = 0;
	right = 1;
	while (left < right)
	{
		i = q[left];
		left++;
		j = i % 5;
		i /= 5;
		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 (val[v[id[max]]] > 0)
			{
				if (j < 4)
				{
					if (dist[v[id[max]]][j + 1] > dist[i][j] + 1)
					{
						dist[v[id[max]]][j + 1] = dist[i][j] + 1;
						q[right] = 5 * v[id[max]] + j + 1;
						right++;
					}
				}
			}
			else
			{
				if (dist[v[id[max]]][0] > dist[i][j] + 1)
				{
					dist[v[id[max]]][0] = dist[i][j] + 1;
					q[right] = 5 * v[id[max]];
					right++;
				}
			}
		}
	}
	int ans = 1e9;
	for (j = 0; j < 5; j++)
		if (ans > dist[n - 1][j])
			ans = dist[n - 1][j];
	if (ans > 1e7)
		ans = -1;
	printf("%d\n", ans);
	return 0;
}