const input = 'dude whats up yo';
const vowels = ['a', 'e', 'i', 'u', 'o'];
let resultArray = [];


for (let i=0; i< input.length; i++){
/* prints each item in array
console.log(input[i]);
 prints index of each item in array
console.log(i);
*/

for(let j=0; j<vowels.length; j++){
  if(input[i]===vowels[j]){
    if(input[i]==='e'){
      resultArray.push('ee')
    }
    else if (input[i]==='u'){
      resultArray.push('uu');
    }
    else{
      resultArray.push(input[i]);
    }
  }
}
}
console.log(resultArray.join('').toUpperCase());