题解 | #访友#

import java.util.*;
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int x = sc.nextInt();
        int cnt = x / 5;
        if(x % 5 != 0) {
            cnt++;
        }
        System.out.println(cnt);
    }
}