python - 没有反转功能的反转字符串

Question

对于输入文本，我必须计算所有元音，将每个单词中的第一个字母大写并反向输出文本(不必大写)，而不使用标题或反向函数。我能够计算出元音的数量，但计算出其他两个元音的数量却很困难。

def main():

    vowelCount = 0
    text = 'abc'

    while(len(text) != 0):
        text = input('Please etner some text or press <ENTER> to exit: ')

        for char in text:
            if char in 'aeiouAEIOU':
                vowelCount += 1
        print('Vowels:', vowelCount)
        vowelCount = 0



        for i in text:
            i = text.find('') + 1
        print(i)

        print(text[0].upper() + text[1:])


main()   

Answer 1

下面是两个反转字符串的示例。 对字符串进行切片

>>> s = 'hello'
>>> reversed_s = s[::-1]

或者使用循环。

res = ''
for char in s:
    res = char + res

<小时/>

完整代码

def main():
    # Run infinitely until break or return
    # it's more elegant to do a while loop this way with a condition to
    # break instead of setting an initial variable with random value.
    while True:
        text = input('Please enter some text or press <ENTER> to exit: ')
        # if nothing is entered then break
        if not text:
            break

        vowelCount = 0
        res = ''
        prev_letter = None

        for char in text:
            if char.lower() in 'aeiou':
                vowelCount += 1
            # If previous letter was a space or it is the first letter
            # then capitalise it.
            if prev_letter == ' ' or prev_letter is None:
                char = char.upper()

            res += char # add char to result string
            prev_letter = char # update prev_letter

        print(res) # capitalised string
        print(res[::-1]) # reverse the string
        print('Vowel Count is: {0}'.format(vowelCount))

# Example
Please enter some text or press <ENTER> to exit: hello world!
Hello World!
!dlroW olleH
Vowel Count is: 3