题解 | 买橘子
买橘子
https://www.nowcoder.com/practice/73e0552b78474a9086781e47f4e01d73
n = int(input())
g = n // 8
y = n % 8
if y == 2 or y == 4 or y == 6:
g = g + 1
elif y == 0:
g = g
else:
g = -1
if n == 2 or n == 4 or n == 10:
g = -1
print(g)
