t = gets.chomp.split(':').map &:to_i                 
minute = t[0] * 60 + t[1]                                         
minute_twice = minute + 5                                          
new_hour = minute_twice / 60; new_hour = 0 if new_hour == 24
new_minute = minute_twice % 60
puts format "%02d:%02d", new_hour, new_minute