<?php
$date = date_create("now");
$input=explode(":",(fgets(STDIN)));
$min=(int)$input[1]+5;
$hour=(int)$input[0];
if($min>=60){
  $min=sprintf('%02d',$min-60);
  $hour=1+(int)$input[0];
  if($hour>=24){
    $hour=sprintf('%02d',$hour-24);
  }else{
    $hour=sprintf('%02d',$hour);
  }
}else{
  $min=sprintf('%02d',$min);
  $hour=sprintf('%02d',$hour);
}
date_time_set($date,$hour,$min);
echo date_format($date, 'H:i') . "\n";