打印出如下图案（菱形）

# -*- coding: UTF-8 -*-
"""
打印出如下图案（菱形）:
   *
  ***
 *****
*******
 *****
  ***
   *
"""


def __print__(n):
    for i in range(n / 2):
        print " " * (n / 2 - 1 - i) + "*" * (2 * i + 1)

    for i in range(n / 2-1, 0, -1):
        print " " * (n / 2 - i) + "*" * (2 * i-1)


__print__(19)

未作奇数偶数判断