In [1]:

    

print ("Hello World")


    

    
Out[1]:





4

In [3]:

    

>>> 2 + 2


    

    
Out[3]:





4

In [4]:

    

>>> 4 - 2


    

    
Out[4]:





2

In [6]:

    

>>> 2 * 2


    

    
Out[6]:





4

In [9]:

    

>>> 7 / 3 # Division always returns a floating number


    

    
Out[9]:





2.3333333333333335

In [7]:

    

>>> 5 // 2 # Floor Division


    

    
Out[7]:





2

In [8]:

    

>>> 7 % 3 # Remainder


    

    
Out[8]:





1

In [10]:

    

>>> 2 ** 4 # Square


    

    
Out[10]:





16

In [11]:

    

>>> 5 ** 7 # 5 to the powder of 7


    

    
Out[11]:





78125

In [14]:

    

>>> width = 5
>>> height = 7
>>> width * height # "=" is used to assign a value to variable


    

    
Out[14]:





35

In [15]:

    

>>> n


    

    




---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
<ipython-input-15-fe13119fb084> in <module>()
----> 1 n

NameError: name 'n' is not defined

In [16]:

    

>>> 3.5 * 2.7


    

    
Out[16]:





9.450000000000001

In [17]:

    

>>> 3.5 * 2


    

    
Out[17]:





7.0

In [20]:

    

>>> tax = 12.5 / 100
>>> price = 100.50
>>> price * tax
>>> price + _
>>> round ( _ , 2 ) ###"_"代表最后一个算出来的数


    

    
Out[20]:





12.56