如何在Python中检查字符串中是否包含某些相同的字符？

Question

In my program, when a user inputs a word, it needs to be checked for letters that are the same.

For example, in string = "hello" , hello has 2 'l's. How can i check for this in a python program?

Answer 1

Use a Counter object to count characters, returning those that have counts over 1.

from collections import Counter

def get_duplicates(string):
    c = Counter(string)
    return [(k, v) for k, v in c.items() if v > 1]

---

In [482]: get_duplicates('hello')
Out[482]: [('l', 2)]

In [483]: get_duplicates('helloooo')
Out[483]: [('l', 2), ('o', 4)]

Answer 2

You can accomplish this with

d = defaultdict(int)

def get_dupl(some_string):
    # iterate over characters is some_string
    for item in some_string:
        d[item] += 1
    # select all characters with count > 1
    return dict(filter(lambda x: x[1]>1, d.items()))

print(get_dupl('hellooooo'))

which yields

{'l': 2, 'o': 5}