Php 최소의 문자열

설정한 최소한 캐릭터에 값을 php

if (strlen($input) < 12)
{
   echo "Input is too short, minimum is 12 characters (20 max).";
}
elseif(strlen($input) > 20)
{
   echo "Input is too long, maximum is 20 characters.";
}