import heapq
import sys
input = sys.stdin.readline
N, M, K = map(int, input().split())
A = list(map(int, input().split()))
G = [[] for _ in range(N)]
for _ in range(M):
    u, v = map(int, input().split())
    u-=1
    v-=1
    heapq.heappush(G[u], (A[v], v))
    heapq.heappush(G[v], (A[u], u))
dp = []
for i, a in enumerate(A):
    heapq.heappush(dp, (a, i))
while len(dp)>1:
    a, i = heapq.heappop(dp)
    s, j = heapq.heappop(G[i])
    if s-a>K:
        print("No")
        exit()
    heapq.heappop(G[j])
    if len(G[i])<len(G[j]):
        for g in G[i]:
            heapq.heappush(G[j], g)
    else:
        for g in G[j]:
            heapq.heappush(G[i], g)
        G[j] = G[i]
print("Yes")