// source https://jsbin.com/gavovuh

index.html

<script id="jsbin-javascript">
//Challenge 11
//Change every letter of the string to the one that follows it and capitalize the
//Vowels

function letterChanges(str){
  
  let newStr = str.toLowerCase().replace(/[a-z]/gi, function(char)
  {
    if(char === 'z' || char === 'Z')
      {
        return 'a';
      } else 
      {
        return String.fromCharCode(char.charCodeAt() + 1);
      }
  });
  
  newStr = newStr.replace(/a|e|i|o|u/gi, function(vowel) {
    return vowel.toUpperCase();
  });
  
  return newStr;
}

const output = letterChanges('Hello There');
 console.log(output);
</script>


<script id="jsbin-source-javascript" type="text/javascript">//Challenge 11
//Change every letter of the string to the one that follows it and capitalize the
//Vowels

function letterChanges(str){
  
  let newStr = str.toLowerCase().replace(/[a-z]/gi, function(char)
  {
    if(char === 'z' || char === 'Z')
      {
        return 'a';
      } else 
      {
        return String.fromCharCode(char.charCodeAt() + 1);
      }
  });
  
  newStr = newStr.replace(/a|e|i|o|u/gi, function(vowel) {
    return vowel.toUpperCase();
  });
  
  return newStr;
}

const output = letterChanges('Hello There');
 console.log(output);
</script>

jsbin.gavovuh.js

//Challenge 11
//Change every letter of the string to the one that follows it and capitalize the
//Vowels

function letterChanges(str){
  
  let newStr = str.toLowerCase().replace(/[a-z]/gi, function(char)
  {
    if(char === 'z' || char === 'Z')
      {
        return 'a';
      } else 
      {
        return String.fromCharCode(char.charCodeAt() + 1);
      }
  });
  
  newStr = newStr.replace(/a|e|i|o|u/gi, function(vowel) {
    return vowel.toUpperCase();
  });
  
  return newStr;
}

const output = letterChanges('Hello There');
 console.log(output);