<?php
 
// your code goes here
function makeRandomizerWithMemory() {
	$memory = array();
	$getValue = function($key) use (&$memory) {
		if (!array_key_exists($key, $memory)) {
			$memory[$key] = mt_rand();
		}
		return $memory[$key];
	};
	return function($arg = null) use ($getValue) {
		if ($arg) {
			$key = strval($arg);
			return $getValue($arg);
		}
		return mt_rand();
	};
}
 
$getRand = makeRandomizerWithMemory();
 
$args = array('sobaka', 'kot', 12345, null);
 
foreach ($args as $arg) {
	echo "{$arg}: {$getRand($arg)}\n";
	echo "{$arg}: {$getRand($arg)}\n\n";
}

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