5. 345. Reverse Vowels of a String

class Solution {
    public String reverseVowels(String s) {
        int i=0, j=s.length()-1;
        char[] arr = s.toCharArray();
        while(i<j){
            boolean flag = true;
            if(!isVowel(s.charAt(i))){
                i++;
                flag=false;
            }

            if(!isVowel(s.charAt(j))){
                j--;
                flag=false;
            }

            if(i<j && flag==true){
                char ch = arr[i];
                arr[i]=arr[j];
                arr[j]=ch;
                i++;j--;

                
            }
        }
        return new String(arr);
    }

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