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  • 序列

    序列是具有先后关系的一组元素

     

     s[0]:第0个位置

    >>> s ='123456'
    >>> s[0:2]
    '12'
    >>> s[::2]
    '135'
    >>> s*3
    '123456123456123456'
    >>> t='cv'
    >>> s+t
    '123456cv'
    >>> '1' in s
    True
    >>> A =[1 ,2, 3]
    >>> A
    [1, 2, 3]
    >>> A=A[:2]
    >>> A
    [1, 2]
    >>> A[1]
    2

    列表

     

    xs = [1,2,3]
    print(xs,xs[2])
    print(xs[-1])
    xs[2]='too'
    print(xs)
    xs.append('good')
    print(xs)
    x = xs.pop()
    print(x,xs)
    [1, 2, 3] 3
    3
    [1, 2, 'too']
    [1, 2, 'too', 'good']
    good [1, 2, 'too']
    >>> ls = ['ac','da','dvv']
    >>> la.append('sf')
    Traceback (most recent call last):
      File "<pyshell#93>", line 1, in <module>
        la.append('sf')
    NameError: name 'la' is not defined
    >>> ls.append('acd')
    >>> ls
    ['ac', 'da', 'dvv', 'acd']
    >>> ls.insert(0,'dvs')
    >>> ls
    ['dvs', 'ac', 'da', 'dvv', 'acd']
    >>> a = ls.pop(1)
    >>> a
    'ac'
    >>> ls
    ['dvs', 'da', 'dvv', 'acd']
    >>> ls = ['a','a','c','d','c']
    >>> ls.remove('a')
    >>> ls
    ['a', 'c', 'd', 'c']
    >>> ls.remove('c')
    >>> ls
    ['a', 'd', 'c']
    >>> ls.reverse()
    >>> ls
    ['c', 'd', 'a']

     

     del ls[i:j:k] [i:j] 左闭右开

    >>> ls[0:3:2]=['96','36']
    >>> ls
    ['96', 'waf', '36', 'vgf']
    >>> del ls[0]
    >>> ls
    ['waf', '36', 'vgf']
    >>> del ls[0:3:2]
    >>> ls
    ['36']
    >>>  ls+=['afv','d','vs']
    SyntaxError: unexpected indent
    >>> ls+=['afv','d','vs']
    >>> ls
    ['36', 'afv', 'd', 'vs']
    >>> ls*=2
    >>> ls
    ['36', 'afv', 'd', 'vs', '36', 'afv', 'd', 'vs']

     Slicing:

    >>> s = ['dcv','vfs','123']
    >>> s[::-1]
    ['123', 'vfs', 'dcv']
    >>> s='123466'
    >>> len(s)
    6
    >>> min(s)
    '1'
    >>> max(s)
    '6'
    >>> s.index('6')
    4
    >>> s.index('6',0,3)
    Traceback (most recent call last):
      File "<pyshell#64>", line 1, in <module>
        s.index('6',0,3)
    ValueError: substring not found
    >>> s.count('6')
    2

    元组

     >>> cre = 'a','b','c'
    >>> cre
    ('a', 'b', 'c')
    >>> cer = (cre,0x10,'red')
    >>> cer
    (('a', 'b', 'c'), 16, 'red')

    >>> cer[0][1]
    'b'

    #获取多个输入的数字
    def get():
        num= []
        isn  = input('请输入数字: ')
        while isn !='':
            num.append(eval(isn))
            isn  = input('请输入数字: ')
            #isn  = eval(input('请输入数字: '))是错的,不能eval(空)
        return num
    print(get())
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  • 原文地址:https://www.cnblogs.com/tingtin/p/11877856.html
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