function padIt(str,n){
  var output = str;
  var padding = "*";
  var idx = 0;

  while (n > 0) {
    if (idx % 2 === 0) {
    // add padding to right side of str
        output[str.length - 1] = padding;
    } else {
        
    // add padding to left side of str
      output[0] = padding;
    }
    idx += 1;
    n -= 1;
  }
  return output;
}