#include using namespace std; int main() { int N, M; cin >> N >> M; vector a(N + 1); int A; for(int i = 0; i < M; i++) { cin >> A; a[A] = 1; } int ans = 0; vector r(N + 1); for(int i = N; i >= 1; i--) { if(a[i] == r[i]) ans++; else { for(int j = 1; j * j <= i; j++) { if(i % j == 0) { r[j] = 1 - r[j]; if(j * j != i) r[i / j] = 1 - r[i / j]; } } } } cout << ans << endl; return 0; }