#!/usr/bin/perl -w 

use strict;

if (@ARGV) {
  my $time = 0;
  foreach $time (@ARGV) {
     print "$time: " . localtime($time) . "\n";
  }
} else {
  while (<STDIN>) {
    if (/^\d+$/) {
      printf("%d = %s\n", $_, scalar localtime($_));
    } else {
      while (/\b(\d{9,})(?:\.\d\d\d)?\b/) {
        $_ = $` . scalar(localtime($1)) . $';
      }
      print($_);
    }
  }
}