// http://infoarena.ro/problema/light2
#include <fstream>
using namespace std;

#define maxSize 1000000

ifstream in("light2.in");
ofstream out("light2.out");

int length,kids,tmp;
int counter;
bool light[maxSize];

int main() {
    in >> length;
    in >> kids;

    for(int i=1;i<=kids;i++) {
        in >> tmp;

        for(int k=tmp;k<=length;k+=tmp)
            if(light[k]) {
                light[k] = false;
                counter--;
            }
            else {
                light[k] = true;
                counter++;
            }
    }

    out << counter;

    in.close();
    out.close();
}