题解 | #访友#

import java.io.*;
import java.util.*;

public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int res = fun(n);
        System.out.println(res);
    }

    public static int fun(int n){
        if(n <= 5){
            return 1;
        }

        int[] dp = new int[n + 1];

        for(int i = 1; i <= n; ++i){
            if(i <= 5){
                dp[i] = 1;
            }else{
                dp[i] = 1 + dp[i - 5];
            }
        }

        return dp[n];
    };
}