#2000

Reverse Prefix of Word

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Description

Given a 0-indexed string word and a character ch, locate the first occurrence of ch in word and reverse the prefix of word from index 0 up to and including that position. If ch is not found, leave word unchanged.

For example, word = "abcdefd" with ch = "d" yields "dcbaefd" (the prefix "abcd" reversed).

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".

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