too long

Below is the code of php which is not working.

<?php
if($_POST[submit]=='Save' || strlen($_POST['testid'])>0)
{
  extract($_POST);
  mysql_query("insert into mst_deff(test_id,sub_id,deff_que,ans) values ('$testid','$subid','$addque','$ans')",$cn) or die(mysql_error());
  echo "<p align=center>Question Added Successfully.</p>";
  echo "hi";
  unset($_POST);
}
?>

i have used echo statement for debugging but it is not showing on the screen that means the if part is not working.