<?php
$mass = array(10, 20, 100, 30, 40, 101, 200, 202, 32);
$lastValue1 = $mass[0];
$lastValue2 = $mass[1];
$lastDef = abs($mass[0] - $mass[1]);
foreach ($mass as $key => $value)
{	
 
 for ($i = 0; $i < count($mass); $i++)
 {
 	$def = abs ($value - $mass[$i]);
 	if ($def == 0)
 	{
		continue;
	}
	if ($def < $lastDef)
	{
		$lastDef = $def;
		$lastValue1 = $value;
		$lastValue2 = $mass[$i];
 
	}
 }
 
}
echo "$lastValue1<br>";
echo "$lastValue2<br>";
 
?>

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