#!/usr/bin/perl

use strict;
use warnings;

sub time_to_str {
  my ($sec, $min, $hour, $mday, $mon, $year) = localtime(shift);
  return sprintf "%04d%02d%02d%02d%02d%02d", $year+1900, $mon+1, $mday
+, $hour, $min, $sec;
}

sub find_time {
  my $tstr = shift;
  my $max = 2**31;
  my $min = 0;
  while ($max != $min) {
    my $mid = int (($max + $min) / 2);
    my $midstr = time_to_str $mid;
    if ($tstr gt $midstr) {
      $min = $mid + 1;
    }
    else {
      $max = $mid;
    }
  }
  return $max;
}

sub add_seconds {
  my ($timestr, $seconds) = @_;
  my $time = find_time $timestr;
  return time_to_str($time + $seconds)
}

while (<DATA>) {
  next if /^\s*(?:#.*)?$/;

  my ($date, $seconds) = split;
  printf "%s + %ds = %s\n", $date, $seconds, add_seconds($date, $secon
+ds);
}

__DATA__
# YYYYMMDDhhmmss        seconds
20060413020000          900
20060413024500          900
20061231235700          900
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