#include <stdio.h>

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