<?php /*   indraginanjar@gmail.com   17 Januari 2014 */ function local_var($num){  $local_num = $num;  return $local_num + 3; }  function function_param($num){  return $num + 3; }  function global_var($num){  global $number;  return $number + 3; }  $number = 4; $count = 1000000; $lengths = array();  $local_start = microtime(true); for($i = 0; $i  $local_time = $local_end - $local_start));  $function_param_start = microtime(true); for($i = 0; $i  $function_param_end - $function_param_start));  $global_var_start = microtime(true); for($i = 0; $i  $global_var_end - $global_var_start));  echo "# Test:\n\n"; echo "## Using Local Variable\n"; echo '  start:', $local_start, "\n"; echo '  end:', $local_end, "\n\n"; echo '  length:', $lengths['local_var'], "\n\n";  echo "## Using Function Parameter Only\n"; echo '  start:', $function_param_start, "\n"; echo '  end:', $functi...