杨辉三角变形（算法）

 public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner(System.in);
        while(sc.hasNext()){
           Integer integer = sc.nextInt();
            if(integer == 1 || integer == 2){
                System.out.println("-1");
                return;
            }
            if(integer % 4 == 3 || integer % 4 == 1){
                System.out.println("2");
                return;
            }
            if(integer % 4 == 0){
                System.out.println("3");
                return;
            }
            if(integer % 4 == 2){
                System.out.println("4");
                return;
            }
        }
    }