元素访问与切片
例5.1 列表的元素访问与列表切片示例
1 list1=[1,"ok",2,3,"python",["a","b","c"]]
2 print(list1[4],list1[-2]) #结果：python python
3 print(list1[:2],list1[2:]) #结果：[1, 'ok'] [2, 3, 'python', ['a', 'b', 'c']]
4 print(list1[:-4],list1[-4:]) #结果：[1, 'ok'] [2, 3, 'python', ['a', 'b', 'c']]
5 print(list1[::-1]) #结果：[['a', 'b', 'c'], 'python', 3, 2, 'ok', 1]
6 print(list1[-1][1:]) #结果：["b","c"]
7 list1[1]='book' #改变列表元素的值。列表是可改变对象。
8 print(list1)#结果：[1, 'book', 2, 3, 'python', ['a', 'b', 'c']]
9 del list1[1]
10 print(list1) #结果：[1, 2, 3, 'python', ['a', 'b', 'c']]
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