SumSeconds03

import java.util.Scanner;

public class Marketing {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        Scanner console = new Scanner(System.in);
        Integer seconds1 = Integer.parseInt(console.nextLine());
        Integer seconds2 = Integer.parseInt(console.nextLine());
        Integer seconds3 = Integer.parseInt(console.nextLine());
        Integer seconds = seconds1 + seconds2 + seconds3;
        Integer minutes = 0;

        if (seconds>119) {
            minutes+=2;
            seconds = seconds - 120;
        }else if (seconds>59){
            minutes++;
            seconds = seconds-60;

        }if (seconds<10){
            System.out.println(minutes + ":" + "0" + seconds);
        } else {
            System.out.println(minutes + ":" + seconds);
        }
        //code ends here
    }
}