import java.util.Scanner;

public class Main{

  public static void main(String[] ards){
    // Nは整数で受け取るのが前提条件
    Scanner sc = new Scanner(System.in);
    int N = sc.nextInt();
    
    double number = N;
    double print = number / 2 ;

    System.out.println(Math.round(print));
  }


  




}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz