h,m = gets.chomp.split(":").map(&:to_i)
m = m + 5
h = h + m / 60
m = m % 60
h = 0 if h == 24
def fill(n)
    n / 10 == 0 ? "0#{n}" : "#{n}"
end
puts "#{fill(h)}:#{fill(m)}"