题解 | 杨辉三角的变形

import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
         Scanner scanner = new Scanner(System.in);
        while(scanner.hasNext()) {
            int row = scanner.nextInt();
            if(row == 1 || row == 2)
            {
                System.out.println(-1);
            }
            if((row - 3) % 4 == 0)
            {
                System.out.println(2);
            }
            if((row - 3) % 4 == 1)
            {
                System.out.println(3);
            }
            if((row - 3) % 4 == 2)
            {
                System.out.println(2);
            }
            if((row - 3) % 4 == 3)
            {
                System.out.println(4);
            }
        }
    }
}