n pressed. The variable "key" holds the</span>
<span class="comment"> * latest key that was pressed. The variable "key_pressed_flag" is set</span>
<span class="comment"> * when a key is pressed and cleared when a key press is checked.</span>
<span class="comment"> */</span>
<span class="keyword">static</span> <span class="keywordtype">char</span> key, key_pressed_flag;

<span class="keyword">static</span> <span class="keywordtype">void</span>
press_key(<span class="keywordtype">char</span> k)
{
  p