How to find the indexes of all occerences of a character in a string? [duplicate]

问题

I guess the heading is self-explanatory, still, I'll make myself more clear.

I've to find the indexes of every occurrence of a character in a string. For example,

word = "banana"
def indexes(x, word):
    #some code
    return (list of indexes of x character in the word)

output:

indexes('a', word)
>> [1, 3, 5]

How do I get this result?

回答1:

Try this:

word = "banana"
def indexes(x, word):
    output = []
    for i,y in enumerate(word):
        if x == y:
            output.append(i)
    return output

output = indexes("a", word)
print(output)

回答2:

Using list comprehension

enumerate() - method adds a counter to an iterable and returns it in a form of enumerate object.

Ex.

word = "banana"
indexes = [ index for index,x in enumerate(word) if x in 'a' ]
print(indexes)

O/P:

[1, 3, 5]

回答3:

i would do something like this

word = "banana"
def indexes(x, word):
  result = []
  for idx, letter in enumerate(word):
    if letter == x:
      result.append(idx)
  return result

and then