import java.util.*;

public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    long n = sc.nextLong();
    long ans = -1;
    for(long i = 3; i <= 6; i++) {
      if(i != 4) {
        long t = n - i;
        int p = 0;
        while(t % 2 == 0) {
          t /= 2;
          if(t % 2 == 1) p++;
        }
        if(p > 0) {
          ans = i;
          break;
        } 
      }
    }
    System.out.println(ans);
  }
}