def main():
    import sys
    input = sys.stdin.read().split()
    ptr = 0
    N = int(input[ptr])
    ptr += 1
    M = int(input[ptr])
    ptr += 1
    A = list(map(int, input[ptr:ptr + M])) if M > 0 else []
    
    in_A = [False] * (N + 1)
    for a in A:
        in_A[a] = True
    
    sum_prev = [0] * (N + 1)
    x = [0] * (N + 1)
    
    for k in range(1, N + 1):
        if in_A[k]:
            xk = (sum_prev[k] + 1) % 2
        else:
            xk = sum_prev[k] % 2
        x[k] = xk
        
        m = 2 * k
        while m <= N:
            sum_prev[m] += xk
            if sum_prev[m] >= 2:
                sum_prev[m] -= 2
            m += k
    
    total = sum(x[1:N+1])
    print(N - total)

if __name__ == "__main__":
    main()