N, K = map(int, input().split())
A = list(map(int, input().split()))
S = set(A)

sabo = [0] * (N + 1)
for i in reversed(range(1, N+1)):
    c = (N // i) % 2
    for j in range(i, N+1, i):
        c ^= sabo[j]
    if i in S and c == 1:
        continue
    if not i in S and c == 0:
        continue
    sabo[i] = 1

print(sum(sabo))