buy apples

Going to a nearby store to buy apples, the treacherous vendor used a bundling deal, offering only 6-per-bag and 8-per-bag packs (packs not splittable).

But now I just want to buy exactly n apples, and I want to buy as few bags as possible for easy portability. If you can't buy exactly n apples, you won't buy it.

Enter description:

Enter an integer n, indicating that Xiaoyi wants to buy n (1 ≤ n ≤ 100) apples

Output description:

Output an integer indicating the minimum number of bags to buy, or -1 if you can't buy exactly n apples

Input example 1:

20

Output example 1:

3

import java.util.ArrayList;
import java.util.Collections;
import java.util.Scanner;

public class M1 {
	public static void main(String[] args) {
		Scanner scanner =new Scanner(System.in);
		int n=scanner.nextInt();
		ArrayList<Integer> m=new ArrayList<Integer>();
		for (int i = 0; i <= n/6; i++) {
			int s=0;
			double y=(n-6*i)/8.0;
			if (y-(int) y==0) {
				s=(int) (i+y);
				m.add(s);
			}			
		}
		if (m.size()==0) {
			System.out.println(-1);
		}else {
			Collections.sort(m);
			System.out.println(m.get(0));
		}
				
		
	}
}