<?php
 
class Organisation {
 
	private $name;
	private $departments = [];
 
	public function __construct($name) {
		$this->name = $name;		
	}
 
	public function addDepartment(Department $dep) {
		if (!in_array($dep, $this->departments)) {
			$this->departments[] = $dep;	
		}
		else {
			throw new Exception('Organisation already have that department');
		}
	}
 
 
}
 
class Department {
	public function __construct($name) {
		$this->name = $name;
	}
}
 
$vector = new Organisation('Вектор');
 
$dep1 = new Department('dep1');
$vector->addDepartment($dep1);
$vector->addDepartment($dep1);
$dep2 = new Department('dep2');
$vector->addDepartment($dep2);
 
 
var_dump($vector);
 
 

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