#include <bits/stdc++.h>

int main() {
std::string s;
    std::cin >> s;
    int a[2]{};
    a[0] = std::stoi(s);
    std::cin >> s >> s;
    a[1] = std::stoi(s);
int b = a[0] * 60 + a[1] + 5;
printf("%02d:%02d\n", b/60%24, a[1]%60);
}