题解 | #杨辉三角的变形#
杨辉三角的变形
https://www.nowcoder.com/practice/8ef655edf42d4e08b44be4d777edbf43
num = int(input().strip())
import sys
a = num
a1 = [2, 3, 2, 4]
if a <= 2:
print("-1")
sys.exit()
else:
re1 = (a-2)%4
if re1 == 0:
print('4')
else:
print(a1[re1-1])
