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Reverse Vowels of a String

Problem statement​

Given a string s, reverse only all the vowels in the string and return it.

The vowels are 'a', 'e', 'i', 'o', and 'u', and they can appear in both cases.

Example 1:

Input: s = "hello"Output: "holle"

Example 2:

Input: s = "leetcode"Output: "leotcede"

Constraints:

  • 1 <= s.length <= 3 * 105
  • s consist of printable ASCII characters.

My solution​

/**
 * @param {string} s
 * @return {string}
 */
var reverseVowels = function(s) {
    const vowelIndex = []
    const vowels =  new Set(["a", "e", "i", "o", "u"]);
    
    for (let i = 0; i < s.length; i++) {
        const curr = s.charAt(i);
        
        if (vowels.has(curr) || vowels.has(curr.toLowerCase())) {
            vowelIndex.push(curr)
        }
    }
    
    let str= "";
    for (let i = 0; i < s.length; i++) {
        const curr = s.charAt(i);
        
        if (vowels.has(curr) || vowels.has(curr.toLowerCase())) {
            str += vowelIndex.pop();
        } else {
            str += curr;
        }
    }
    
    return str
};