How can I increase 0000 by 1 and keep formatting?

Question

$i=0000;
while($i<=1231)
{
  print "$i";
  $i++;
}

I want it to display 0001, 0002, 0003, 0004, but instead it prints: 0, 1, 2

Does anyone know why this isn't working?
Thank you in advance.

Answer 1

Try using printf("%04s",$i);