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<?php
 // Begin the session
 session_start();
 
 // To avoid case conflicts, make the input uppercase and check against the session value
 // If it's correct, echo '1' as a string
 if(strtoupper($_GET['captcha']) == $_SESSION['captcha_id'])
 echo 'true';
 // Else echo '0' as a string
 else
 echo 'false';
 
 ?>
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