#include <stdio.h>
int main()
{
   int hour,min,k;
   int nowhour ,nowmin;
   scanf("%d:%d %d",&hour ,&min,&k);
   nowhour = (hour + (min+k)/60)%24;
   if((hour + (min+k)/60)%24 ==0)
   {
    nowhour = 0;
    }
     else
     nowhour = (hour + (min+k)/60)%24;
    if((min+k)%60 ==0)
   {
    nowmin=0;
    }
    else
    nowmin=(min+k)%60;
   printf("%02d:%02d",nowhour ,nowmin);
   
   
   
   


}