The title

You are given a string word with subscripts starting at 0 and a character ch. Find the subscript I of the first occurrence of ch and invert the character in Word from subscript 0 to subscript I, including subscript I. If the character CH does not exist in Word, no operation is required.

For example, if word = “abcdefd” and ch = “d”, then you should reverse from subscript 0 to subscript 3 (including 3). The resulting string will be “dcbaefd”. Returns the result string.

Example 1: Input: word = "abcdefd", ch = "d" Output: "dcbaefd" Explanation: "d" first appears at subscript 3. Invert the character from subscript 0 to subscript 3 inclusive, resulting in the string "dcbaefd". Example 2: Input: word = "xyxzxe", ch = "z" Output: "zxyxxe" Explanation: The first and only occurrence of "z" is at subscript 3. Invert the character from subscript 0 to subscript 3, resulting in the string "zxyxxe". Example 3: Input: word = "abcd", ch = "z" Output: "abcd" Explanation: "z" does not exist in word. There is no need to reverse, and the resulting string is "abcd".Copy the code

Tip:

1 <= word. Length <= 250 Word consists of lowercase letters. Ch is a lowercase letter

Their thinking

class Solution:
    def reversePrefix(self, word: str, ch: str) -> str:
        try:
            index = word.index(ch)
            res = word[:index+1][::-1]
            res += word[index+1:]
            # print(res)
            return res
        except:
            return word

if __name__ == '__main__':
    # word = "abcdefd"
    # ch = "d"
    word = "abcd"
    ch = "z"
    result = Solution().reversePrefix(word,ch)
    print(result)

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