<?php
function drop($var, $remove) 
  { 
   
if(count($var) == 1) 
    {
	
return $var; 
    }

  foreach($var as $key => $element) 
    { 
    if($remove) 
      { 
      $remove = false; 
      } 
    else 
      { 
      $remove = true; 
      unset($var[$key]); 
      //echo $var[$key];
      } 

    } 

   
    return drop($var, $remove);
	
  } 

//fill array 
$arychairs = range(1,100); 

//extract survivor from function drop;
$survivor=drop($arychairs, false); 
echo "Survivor is at position ".array_pop($survivor);
?>