#include <stdio.h>

int main() {
    int hour, min,howmin;
    scanf("%d:%d %d",&hour,&min,&howmin);
    hour = ((min + howmin)/60+hour)%24;
    min = (min + howmin)%60;
    printf("%02d:%02d\n",hour,min);
    
    
    return 0;
}

%02d保证整数的输出至少为两位，不够两位在左侧补零