题解 | #杨辉三角的变形#

import java.util.Scanner;

public class Main {
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
while (in.hasNextInt()) {
int num = in.nextInt();
if(num == 1 || num == 2){
System.out.println(-1);
continue;
}
else if(num % 4 == 1 || num % 4 == 3){
System.out.println(2);
continue;
}
else if(num % 4 == 0){
System.out.println(3);
continue;
}
else if(num % 4 == 2){
System.out.println(4);
continue;
}
}
}
}