<?php

$handle = fopen ("php://stdin","r");
fscanf($handle,"%d",$n);
$a_temp = fgets($handle);
$a = explode(" ",$a_temp);
array_walk($a,'intval');
// your code goes here
$res = [];
$len = count($a);
foreach($a as $key => $val) {
    $diff = ($key === ($len - 1)) ? $a[$key] - $a[0] : $a[$key] - $a[$key+1];
    $res[] = abs($diff);
}
echo min($res);
?>