题解 | #杨辉三角的变形#

找规律题

public class Main{
	public static void main(String[] args){		Scanner sc = new Scanner(System.in);
		while(sc.hasNext()){
			int a = sc.nextInt();
			if(a<=2){
				System.out.println(-1);
			}
			else if(a%2!=0){
				System.out.println(2);
			}
			else if(a%4==0){
				System.out.println(3);
			}
			else{
				System.out.println(4);
			}
		}
	}
}