python3-列表与字符串

发布时间:2019-09-21 10:43:17编辑:auto阅读(1587)

    del如下。pop弹出元素并返回。

    print(x)
    [1, 2, 5, 6, 8, 4, 3, 5]
    
    del x[3]
    print(x)
    [1, 2, 5, 8, 4, 3, 5]
    
    y=x.pop()
    print(y)
    5
    
    x
    print(x)
    [1, 2, 5, 8, 4, 3]
    print(x)
    [1, 2, 5, 8, 4, 3]
    
    x
    z=x.pop(3)
    print(x)
    [1, 2, 5, 4, 3]
    
    z
    print(z)
    8
    x1=(1,2,"aaaa")
    x2=(3,4,"bbbb")
    
    x1,x2
    print(x1,x2)
    (1, 2, 'aaaa') (3, 4, 'bbbb')
    x1
    (1, 2, 'aaaa')
    
    x2
    x2
    (3, 4, 'bbbb')
    
    print(x1[0],x1[1])
    1 2
    
    print(x2[2],x1[1])
    bbbb 2
    
    ```python
    str='1234\n5aaaaa'
    print(str)
    str="123\n45'aaaa'a"
    print(str)
    
    
    1234
    5aaaaa
    123
    45'aaaa'a
    str="""
    adfdf
    {asdf}
    //2qerffasda
    """
    print(str)
    str='''adfdf
    {asdf}
    //2qerffasda'''
    print(str)
    adfdf
    {asdf}
    //2qerffasda
    
    adfdf
    {asdf}
    //2qerffasda
    str="""123\n45'aaaa'a"""
    print(str)
    str='''123\n45'aaaa'a'''
    print(str)
    str='''
    123\n45'aaaa'a
    '''
    print(str)
    123
    45'aaaa'a
    123
    45'aaaa'a
    
    123
    45'aaaa'a
    str='''
    123\n
    45'aaaa'a
    '''
    print(str)
    123
    
    45'aaaa'a

    可见三引号中转义字符还是有作用,但使用r则可以消除转义字符的作用

    str='''
    123\n
    45'aaaa'a
    aa\\
    bb
    '''
    print(str)
    str=r'''
    123\n
    45'aaaa'a
    aa\\
    bb
    '''
    print(str)
    123
    
    45'aaaa'a
    aa\
    bb
    
    123\n
    45'aaaa'a
    aa\\
    bb
    s="ssadf"
    print(s)
    del s
    print(s)
    ssadf
    ---------------------------------------------------------------------------
    NameError                                 Traceback (most recent call last)
    <ipython-input-1-3dfd4f621ec7> in <module>
          2 print(s)
          3 del s
    ----> 4 print(s)
    
    NameError: name 's' is not defined

    print(x)
    x3=tuple(x)
    print(x3)
    [1, 2, 5, 4, 3, 10, 20, [1, 2]]
    (1, 2, 5, 4, 3, 10, 20, [1, 2])

    print(x3[5],x3[6])
    10 20

    1
    print(x[7][0])
    print(x[7][1])
    1
    2

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