#include <bits/stdc++.h>

using namespace std;

int main() {
    int h, m;
    scanf("%d:%d", &h, &m);
    int mm = (m + 5) % 60;
    int hh = (h + (m+5) / 60) % 24;

    printf("%02d:%02d\n", hh, mm);
    return 0;
}