题目：编写一个函数，输入n为偶数时，调用函数求1/2+1/4+...+1/n,当输入n为奇数时，调用函数1/1+1/3+...+1/n
实例(Python 2.0+)
#!/usr/bin/python
# -*- coding: UTF-8 -*-
def peven(n):
i = 0
s = 0.0
for i in range(2,n + 1,2):
s += 1.0 / i # Python里，整数除整数，只能得出整数，所以需要使用 浮点数 1.0
return s
def podd(n):
s = 0.0
for i in range(1, n + 1,2):
s += 1.0 / i # Python里，整数除整数，只能得出整数，所以需要使用 浮点数 1.0
return s
def dcall(fp,n):
s = fp(n)
return s
if __name__ == '__main__':
n = int(raw_input('input a number:\n'))
if n % 2 == 0:
sum = dcall(peven,n)
else:
sum = dcall(podd,n)
print (sum)
Traceback (most recent call last):
File "D:\练习\76.py", line 22, in
n = int(raw_input('input a number:\n'))
NameError: name 'raw_input' is not defined
