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 = [0] * N for y in x: infected[y] = 0 heappush(heap, (s[y], y)) ans = 0 while heap: t, v = heappop(heap) if removed[v]: continue for u in G[v]: if t >= infected[u] + P or removed[u]: continue if infected[u] == INF: infected[u] = t heappush(heap, (t + s[u], u)) else: removed[u] = 1 ans += 1 print(ans)