let out = [];
function getCommonElements(array1, array2) {
   for(i = 0; i < 100; i++){
      if(array1.includes(i) && array2.includes(i)) out.push(i);
   }
   return out;
}
result = getCommonElements([24, 12, 27, 3], [12, 8, 3, 36, 27]);
console.log(result);

run: