def main():
    import sys
    input = sys.stdin.read().split()
    idx = 0
    N = int(input[idx])
    idx += 1
    M = int(input[idx])
    idx += 1
    A = []
    if M > 0:
        A = list(map(int, input[idx:idx+M]))
        idx += M
    
    # Compute d[j] for j from 1 to N
    d = [0] * (N + 1)
    for i in range(1, N + 1):
        for j in range(i, N + 1, i):
            d[j] += 1
    
    # Compute is_prime and mu[j]
    is_prime = [True] * (N + 1)
    is_prime[0] = is_prime[1] = False
    mu = [1] * (N + 1)
    for i in range(2, N + 1):
        if is_prime[i]:
            # Mark multiples of i^2
            j = i * i
            while j <= N:
                mu[j] = 0
                j += i * i
            # Mark multiples of i
            for j in range(i, N + 1, i):
                if mu[j] != 0:
                    mu[j] *= -1
            # Sieve of Eratosthenes to mark non-primes
            j = i * i
            while j <= N:
                is_prime[j] = False
                j += i
    
    # Compute s[j]
    s = [0] * (N + 1)
    A_set = set(A)
    for j in A_set:
        s[j] = 1
    
    # Compute c[j]
    c = [0] * (N + 1)
    for j in range(1, N + 1):
        c[j] = (d[j] - s[j]) % 2
    
    # Precompute divisors for each i
    divisors = [[] for _ in range(N + 1)]
    for k in range(1, N + 1):
        for i in range(k, N + 1, k):
            divisors[i].append(k)
    
    # Compute x_i
    total_skipped = 0
    for i in range(1, N + 1):
        sum_xi = 0
        for k in divisors[i]:
            m = i // k
            sum_xi += mu[k] * c[m]
        x_i = sum_xi % 2
        total_skipped += x_i
    
    print(total_skipped)

if __name__ == "__main__":
    main()