2000. Reverse Prefix of Word

[F4NT0]

Given a 0-indexed string word and a character ch, reverse the segment of word that starts at index 0 and ends at the index of the first occurrence of ch (inclusive). If the character ch does not exist in word, do nothing.

For example, if word = "abcdefd" and ch = "d", then you should reverse the segment that starts at 0 and ends at 3 (inclusive). The resulting string will be "dcbaefd".
Return the resulting string.

Example 1:

• Input: word = "abcdefd", ch = "d"
• Output: "dcbaefd"
• Explanation: The first occurrence of "d" is at index 3.
• Reverse the part of word from 0 to 3 (inclusive), the resulting string is "dcbaefd".

Example 2:

• Input: word = "xyxzxe", ch = "z"
• Output: "zxyxxe"
• Explanation: The first and only occurrence of "z" is at index 3.
• Reverse the part of word from 0 to 3 (inclusive), the resulting string is "zxyxxe".

Example 3:

• Input: word = "abcd", ch = "z"
• Output: "abcd"
• Explanation: "z" does not exist in word.
• You should not do any reverse operation, the resulting string is "abcd".

Constraints:

• 1 <= word.length <= 250
• word consists of lowercase English letters.
• ch is a lowercase English letter.