python 基础 —— collections.Counter（）

In [1]: from collections import Counter

In [2]: p='asdsaddsdasda'

In [3]: Counter(p)
Out[3]: Counter({'a': 4, 'd': 5, 's': 4})

In [4]: type(Counter(p))
Out[4]: collections.Counter

In [5]: dict(Counter(p))
Out[5]: {'a': 4, 'd': 5, 's': 4}

In [6]: p
Out[6]: 'asdsaddsdasda'

In [7]: p[:1]
Out[7]: 'a'

In [8]: s='asdsaddsdasda'

In [9]: p='as'

In [10]: res=[]

In [11]: pCounter = Counter(p)

In [12]: sCounter = Counter(s)

In [13]: sCounter = Counter(s[:len(p)-1])

In [14]: sCounter
Out[14]: Counter({'a': 1})

In [15]: sCounter[s[2]] += 1

In [16]: sCounter
Out[16]: Counter({'a': 1, 'd': 1})