package main

import (
	"fmt"
	"strconv"
	"strings"
)

func main() {
	var t string
	fmt.Scan(&t)
	ts := strings.Split(t, ":")
	h, _ := strconv.Atoi(ts[0])
	m, _ := strconv.Atoi(ts[1])
	m += 5
	if m >= 60 {
		h++
		m = m % 60
	}
	if h >= 24 {
		h = h % 24
	}
	fmt.Printf("%02d:%02d\n", h, m)
}