package main

import (
	"fmt"
	"strconv"
)

func main() {
	var t string
	fmt.Scan(&t)
	h, _ := strconv.Atoi(t[0:2])
	m, _ := strconv.Atoi(t[3:5])
	nm := (m + 5) % 60
	nh := (h + (m+5)/60) % 24
	fmt.Printf("%02d:%02d\n", nh, nm)
}