#include <stdio.h>
//需要注意的是小时最大是24,超过24小时的要对24小时取模
int main() {
    int hour,minute;
    long long k;
    scanf("%d:%d %lld",&hour,&minute,&k);
    int new = k / 60;
    int newhour = hour + new;
    int new1 = k % 60;
    int newminute = new1 + minute;
    while(newminute >= 60)
    {
        newminute -= 60;
        newhour += 1;
    }
    newhour %= 24;
    printf("%02d:%02d\n",newhour,newminute);
    return 0;
}