#python2
>>> a = 13
>>> a
13
>>> type(a)
<type 'int'> //整型
>>> a = 1234124512512341235124512512
>>> type(a)
<type 'long'> //长整型
#python3
>>> a = 13
>>> type(a)
<class 'int'>
>>> a = 1245123512512561251245124124124
>>>
>>> type(a)
<class 'int'>
>>> a = 'hello'
>>> a
'hello'
>>> a.center(40)
' hello '
>>> a.center(40,'*') //按照一定格式输出
'*****************hello******************'
>>> print("学生管理系统".center(50,'-'))
----------------------学生管理系统----------------------
>>> print("学生管理系统".center(50,'*'))
**********************学生管理系统**********************
>>> a = 1
>>> float(a)
1.0
>>> b = 2.3
>>> int(b)
2
>>> float(b)
2.3
>>> str(b)
'2.3'
>>> str = 'westos'
>>> float(str)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ValueError: could not convert string to float: 'westos'
#删除内存中的变量
>>> a = 1.2
>>> a
1.2
>>> del a
>>> a
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
NameError: name 'a' is not defined
#布尔数据类型
>>> a = 'hello'
>>> bool(a)
True
>>> bool(0)
False
>>> b = ''
>>> b
''
>>> bool(b)
False