import java.util.*;
 public class Main {
	public static void main(String[] args){
      Scanner sc = new Scanner(System.in);

      int N = sc.nextInt();
      int count = 0;
     
      while(N > 0){
      N -= 2;
      count++;
     }

      System.out.print(count);
   }
 }
/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