(JAVA) 백준 2839 설탕 배달 - Dynamic Programming

import java.util.Scanner;

public class T2 {

	public static void main(String args[]){


		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		int count = 0; 
		sc.close();

		while(true) {
			if (N % 5 ==0) {
				System.out.println(N/5 + count);
				break;
			}else if(N <= 0) {
				System.out.println(-1);
				break;
			}
			N = N-3;
			count++;
		}
	}

}