#include <stdio.h>

int main() 
{
    int hour,minute,k;
    scanf("%d:%d %d",&hour,&minute,&k);   
    hour = (hour+(minute+k)/60)%24;     //注意时是否超过24
    minute = (minute+k)%60;
    printf("%02d:%02d",hour,minute);
    return 0;
}