import java.io.*;
import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner();
        int n = sc.nextInt();
        int m = sc.nextInt();
        boolean[] isOpen = new boolean[n + 1];
        for (int i = 0; i < m; i++) {
            isOpen[sc.nextInt()] = true;
        }
        int ans = 0;
        for (int i = n; i >= 1; i--) {
            if (!isOpen[i]) {
                ans++;
                continue;
            }
            for (int j = 2; j <= Math.sqrt(i); j++) {
                if (i % j == 0) {
                    isOpen[j] ^= true;
                    if (j * j < i) {
                        isOpen[i / j] ^= true;
                    }
                }
            }
            isOpen[1] ^= true;
        }
        System.out.println(ans);
    }
}
    
class Scanner {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    StringTokenizer st = new StringTokenizer("");
    StringBuilder sb = new StringBuilder();
    
    public Scanner() throws Exception {
        
    }
    
    public int nextInt() throws Exception {
        return Integer.parseInt(next());
    }
    
    public long nextLong() throws Exception {
        return Long.parseLong(next());
    }
    
    public double nextDouble() throws Exception {
        return Double.parseDouble(next());
    }
    
    public String next() throws Exception {
        while (!st.hasMoreTokens()) {
            st = new StringTokenizer(br.readLine());
        }
        return st.nextToken();
    }
    
}