代码
import collections#counter继承字典的方法,items(),keys(),vavle() obj = collections.Counter('acbdafcbad') print(obj) print(type(obj)) print(obj.most_common(3)) for item in obj.elements(): print(item) for k,v in obj.items(): print(k,v) obj.update(['a','b','b','w','c'])#加元素 print(obj) obj.subtract(['w','c','z'])#减元素 print(obj)
结果:
Counter({'a': 3, 'b': 2, 'd': 2, 'c': 2, 'f': 1}) <class 'collections.Counter'> [('a', 3), ('b', 2), ('d', 2)] a a a b b d d c c f a 3 b 2 d 2 c 2 f 1 Counter({'a': 4, 'b': 4, 'c': 3, 'd': 2, 'w': 1, 'f': 1}) Counter({'a': 4, 'b': 4, 'd': 2, 'c': 2, 'f': 1, 'w': 0, 'z': -1})