ReverseVowelsOfAString.java

package dev.namtx.leetcode.daily;

public class ReverseVowelsOfAString {
    public static void main(String[] args) {
        System.out.println(new ReverseVowelsOfAString().reverseVowels("aA"));
    }

    public String reverseVowels(String s) {
        char[] chars = s.toCharArray();
        int left = 0;
        int right = s.length() - 1;
        while (left < right) {
            if (isVowel(chars[left])) {
                if (isVowel(chars[right])) {
                    // swap
                    char tmp = chars[left];
                    chars[left] = chars[right];
                    chars[right] = tmp;
                    left++;
                }
                right--;
            } else {
                left++;
            }
        }
        StringBuilder sb = new StringBuilder();
        for (char c : chars) {
            sb.append(c);
        }
        return sb.toString();
    }

    private boolean isVowel(char c) {
        if (c == 'a' || c == 'e' || c == 'i' || c == 'o' || c == 'u' || c == 'A' || c == 'E' || c == 'I' || c == 'O' || c == 'U') {
            return true;
        }
        return false;
    }
}