#include <stdio.h>

int main(d) {
    int k;
    int hour,minute;
    scanf("%d:%d %d",&hour,&minute,&k);
    int x = k/60;
    int y = k%60;
    hour = hour+x;
    minute = minute+y;
    if(minute>=60)
    {
        minute = minute-60;
        hour = hour+1;
    }
    if(hour>=23)
    {
        hour = hour%24;
    }
    printf("%02d:%02d",hour,minute);
    return 0;
}