Problem1052--堆木头

1052: 堆木头

Time Limit: 1 Sec  Memory Limit: 128 MB
Submit: 18  Solved: 1
[Status] [Submit] [Creator:]

Description


Input

n          一个整数

Output

一个整数     即堆法数,若不可能,则输出0.

Sample Input Copy

21

Sample Output Copy

3

HINT

Source/Category