#include <stdio.h>

int main() {
    int hour,minute,k;
    scanf("%d:%d%d",&hour,&minute,&k);
    minute+=k%60;
    while(minute>59)
    {
        minute-=60;
        hour+=1;
    }
    hour+=k/60;
    while(hour>23)
    hour-=24;
    printf("%02d:%02d",hour,minute);
    return 0;
}