N, M = map(int, input().split())
a = list(map(int, input().split()))
g = [[] for _ in range(N)]
for i in range(M):
    u, v = map(int, input().split())
    if not a[u - 1] == a[v - 1]:
        g[u - 1].append(a[v - 1])
        g[v - 1].append(a[u - 1])
for i, n in enumerate(g):
    ns = list(set(g[i]))
    length = len(ns)
    if length > 2:
        print('YES')
        exit()
    elif length == 2:
        if (ns[0] < a[i] and ns[1] < a[i]) or (ns[0] > a[i] and ns[1] > a[i]):
            print('YES')
            exit()
print('NO')