python基本数据类型-字典

kuuty

1.创建字典

1	>>> dic = {'k1':'v1','k2':'v2','k3':'v3'}

2.索引

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>>> dic['k1'] 'v1' >>> dic['k2'] 'v2'

3.新增

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>>> dic['k4'] = 'v4' >>> dic {'k3': 'v3', 'k2': 'v2', 'k1': 'v1', 'k4': 'v4'}

4.删除

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>>> del dic['k4'] >>> dic {'k3': 'v3', 'k2': 'v2', 'k1': 'v1'}

5.

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>>> dic.keys() ['k3', 'k2', 'k1'] >>> dic.values() ['v3', 'v2', 'v1'] >>> dic.items() [('k3', 'v3'), ('k2', 'v2'), ('k1', 'v1')]

6.循环

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>>> for k,v in dic.items(): ...   print(k,v) ... ('k3', 'v3') ('k2', 'v2') ('k1', 'v1')

7.长度

1 2	>>> len(dic) 3