import java.util.*;

class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int a = sc.nextInt();
        if ((a * 2) % 2 == 1){
            a = a + 1;
        }

        int b = a/2;
            
        System.out.println(b);
    }
}
