LeetCode 541: Reverse String II

function reverseStr(s: string, k: number): string {
    const charArray = s.split("");

    for (let i = 0; i < charArray.length; i += 2 * k) {
        let start = i;
        let end = Math.min(start + k - 1, charArray.length);

        while (start < end) {
            [charArray[start], charArray[end]] = [charArray[end], charArray[start]];

            ++start;
            --end;
        }
    }

    return charArray.join("");
};