#include <iostream>
#include <string>
#include <sstream>
#include <iomanip>

int main(int argc, char** argv) {
	std::string input;
	std::cin >> input;

	std::stringstream ss(input);
	std::string buffer;

	int hour;
	int min;

	getline(ss, buffer, ':');
	hour = std::stoi(buffer);
	getline(ss, buffer, ':');
	min = std::stoi(buffer);

	min += 5;
	if (min > 59) {
		min -= 60;
		hour++;
		if (hour > 23) {
			hour -= 24;
		}
	}

	std::cout << std::setfill('0') << std::setw(2) << hour << ":";
	std::cout << std::setfill('0') << std::setw(2) << min << std::endl;
}