import java.util.Scanner

//
fun _Do() {
    
    val T = scan.next()// 1-
    
    val hh = T.substring(0, 2).toInt()
    val mm = T.substring(3, 5).toInt()
    
    val new_mm = (mm + 5) % 60
    val new_hh = (hh+(mm+5)/60) % 24
    
    System.out.printf("%02d",new_hh)
    print(":")
    System.out.printf("%02d",new_mm)
    println()
}

var scan = Scanner(System.`in`)
fun main( argv : Array<String> ) {
    _Do()
}

fun strings(N:Int):Array<String> = Array(N,{scan.next()})
fun ints(N:Int):Array<Int> = Array(N,{scan.nextInt()})
fun longs(N:Int):Array<Long> = Array(N,{scan.nextLong()})