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<?php
require_once 'AbstractTrain.php';
 require_once 'Train.php';
 require_once 'Wagon.php';
 
 $newTrain = new Train('Train M1');
 $newTrain->addWagon(new Wagon('Wagon 1'));
 $newTrain->addWagon(new Wagon('Wagon 2'));
 $newTrain->addWagon(new Wagon('Wagon 3'));
 
 $newWagon = new Wagon('Wagon M4');
 
 //U can't add a train to a wagon
 $newWagon->addWagon($newTrain);
 
 //Check Train and Wagon
 $newTrain->check();
 
 echo "<br />";
 
 $newWagon->check();
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