#include <iostream>
#include <algorithm>
#include <string>
#include <cstdio>
using namespace std;

int main()
{
    int h, m;
    scanf("%d:%d", &h, &m);

    h += (m += 5) / 60;

    printf("%02d:%02d\n", h % 24, m % 60);

    return 0;
}