Leetcode: Reverse vowels in the given string.

reverseVowels.java

class Solution {
    public String reverseVowels(String s) {
        var arr = s.toCharArray();
        var l = 0;
        var r = arr.length - 1;
        while (l < r && l < arr.length && r >= 0 ){
            while (l < arr.length && l < r && !isVowel(arr[l])){
                l++;
            }
            while (r >= 0 && l < r && !isVowel(arr[r])){
                r--;
            }
            if (l >= r){
                break;
            }
            var temp = arr[l];
            arr[l] = arr[r];
            arr[r] = temp;
            l++;
            r--;
        }
        var sb = new StringBuilder();
        sb.append(arr);
        return sb.toString();
    }

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

Observation

The above code has been implemented by me. The method isVowel is different from the initial implementation. The first implementation is as follows:

private boolean isVowel(char c){
        return (
            Objects.equals(c, 'a') || Objects.equals(c, 'A') ||
            Objects.equals(c, 'e') || Objects.equals(c, 'E') ||
            Objects.equals(c, 'i') || Objects.equals(c, 'I') ||
            Objects.equals(c, 'o') || Objects.equals(c, 'O') || 
            Objects.equals(c, 'u') || Objects.equals(c, 'U')  
        );
    }

The code with the above implementation of the isVowel method took 7 ms of runtime whereas the implementation mentioned above took 2 ms.