自定義輸入時，提示ValueError: invalid literal for int() with base 10: '10.1'錯誤
>>> a = int(raw_input('please input something:'))
please input something:10.1
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ValueError: invalid literal for int() with base 10: '10.1'
原因是數字字符串不能直接轉int類型，需要轉為float類型后才能轉int類型：
>>> int(float("10.1"))
10
或者：
>>> a = float(raw_input('please input something:'))
please input something:10.1
>>> type(a)
<type 'float'>
>>> int(a)
10