from heapq import heappush, heappop
import sys
input = sys.stdin.readline


N, K, M, P = map(int, input().split())
G = [[] for _ in range(N)]
for _ in range(M):
    u, v = map(int, input().split())
    u -= 1
    v -= 1
    G[u].append(v)
    G[v].append(u)
s = [int(input()) for _ in range(N)]
x = [int(input())-1 for _ in range(K)]
heap = []
INF = 10**10
infected = [INF] * N
removed = [-1] * N
for y in x:
    infected[y] = 0
    heappush(heap, (s[y], y))
ans = 0
while heap:
    t, v = heappop(heap)
    if removed[v] != -1 and removed[v] < t:
        continue
        continue
    for u in G[v]:
        if t >= infected[u] + P or removed[u] != -1:
            continue
        if infected[u] == INF:
            infected[u] = t
            heappush(heap, (t + s[u], u))
        else:
            removed[u] = t
            ans += 1
print(ans)