跟踪列表中元素的频率

Python 计数器跟踪容器中每个元素的频率。Counter() 返回一个以元素为键、以其出现频率为值的字典。

from collections import Counter
list = [1, 2, 3, 2, 4, 3, 2, 3]
count = Counter(list)
print(count) # {2: 3, 3: 3, 1: 1, 4: 1}