n, m = map(int, input().split())
A = list(map(int, input().split()))
edge = []
for _ in range(m):
    u, v = map(int, input().split())
    u -= 1
    v -= 1
    if u > v:
        u, v = v, u
    edge.append((u, v))

for i in range(m):
    u1, v1 = edge[i]
    for j in range(i + 1, m):
        u2, v2 = edge[j]
        if u1 == u2:
            x, y, z = A[v1], A[u1], A[v2]
        elif u1 == v2:
            x, y, z = A[v1], A[u1], A[u2]
        elif v1 == u2:
            x, y, z = A[u1], A[v1], A[v2]
        elif v1 == v2:
            x, y, z = A[u1], A[v1], A[u2]
        else:
            continue
        if x == y or x == z or y == z:
            continue
        if x < y > z or x > y < z:
            print("YES")
            exit()
print("NO")