Reversing vowels in a string JavaScript

JavascriptWeb DevelopmentFront End TechnologyObject Oriented Programming

We are required to write a JavaScript function that takes a string as input and reverse only the vowels of a string.

For example −

If the input string is −

const str = 'Hello';

Then the output should be −

const output = 'Holle';

The code for this will be −

const str = 'Hello'; const reverseVowels = (str = '') => {
   const vowels = new Set(['a','e','i','o','u','A','E','I','O','U']);
   let left = 0, right = str.length-1;
   let foundLeft = false, foundRight = false;
   str = str.split(""); while(left < right){
      if(vowels.has(str[left])){
         foundLeft = true
      };
      if(vowels.has(str[right])){
         foundRight = true
      };
      if(foundLeft && foundRight){
         [str[left],str[right]] = [str[right],str[left]];
         foundLeft = false; foundRight = false;
       }; if(!foundLeft) {
         left++
      }; if(!foundRight) {
         right--
      };
   };
   return str.join("");
};
console.log(reverseVowels(str));

And the output in the console will be −

Holle
raja
Published on 21-Nov-2020 10:21:12
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