hadaytullah

<? php
function high_order_bitmask($wordSize) {
  if($wordSize == 0 or $wordSize == 1){
    return 0;
  }
  $bitmask = 0;
  for($i=$wordSize-1; $i >= $wordSize/2; $i-- ){
    $bitmask += pow(2,$i);
  }
  return $bitmask;

hadaytullah

<? php
function markdown_parser ($markdown) {
  $segments = explode('# ', trim($markdown), 2);
  if(count($segments)>1){
    //adding back the hash that explode removed, this simplifies the logic below
    $segments[0] = $segments[0].'#'; 
    
    //making sure that all are hashes and nothing else at the start of markdown
    $first_array = str_split($segments[0]);
    $unique = array_unique($first_array);