source_code: import java.util.*;
  import java.io.*;
  
  public class programA {
  
  	public static void main(String[] args) throws IOException {
  		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
  		int n = Integer.parseInt(br.readLine());
  		if(n%2 == 0)System.out.println(n/2 +1);
  		else System.out.println((int)Math.ceil((double)n/2));
  	}
  }
  
  
  
  
  