from collections import defaultdict, deque

INF = 1 << 60
N, M = map(int, input().split())
adj = defaultdict(list)
for _ in range(M):
    u, v = map(lambda x: int(x)-1, input().split())
    adj[u].append(v)
    adj[v].append(u)

L = int(input())
q = deque()
for _ in range(L):
    J, K = map(int, input().split())
    J -= 1
    q.append((J, K))

monitored = set()
while q:
    v, k = q.popleft()
    if v in monitored: continue
    monitored.add(v)

    if k == 0: continue
    for to in adj[v]:
        if to in monitored: continue
        q.append((to, k-1))


dists = [INF] * N
q = deque([0])
dists[0] = 0
while q:
    v = q.popleft()
    if v == N-1:
        print('Yes')
        print(dists[v])
        break

    for to in adj[v]:
        if to in monitored: continue
        if dists[to] > dists[v] + 1:
            dists[to] = dists[v] + 1
            q.append(to)
else:
    print('No')