백준 BOJ 2839번 - 설탕 배달

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코드

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int n = in.nextInt();

        if (n == 4 || n == 7) 
            System.out.println(-1);
        else if (n % 5 == 0) 
            System.out.println(n / 5);
        else if (n % 5 == 1 || n % 5 == 3) 
            System.out.println((n / 5) + 1);
        else if (n % 5 == 2 || n % 5 == 4) 
            System.out.println((n / 5) + 2);
    }
}