#define _USE_MATH_DEFINES

#include <iostream>		//cin, cout
#include <vector>		//vector
#include <algorithm>	//sort,min,max,count
#include <string>		//string,getline, to_string
#include <cstdlib>		//abs(int)
#include <utility>		//swap, pair
#include <deque>		//deque
#include <climits>		//INT_MAX
#include <bitset>		//bitset
#include <cmath>		//sqrt, ceil. M_PI, pow, sin
#include <ios>			//fixed
#include <iomanip>		//setprecision
#include <sstream>		//stringstream
#include <numeric>		//gcd, assumlate
#include <random>		//randam_device
#include <limits>		//numeric_limits

using namespace std;
constexpr long long int D_MOD = 1000000007;

inline vector<string> SplitString(const string& str, const char key) {
	//文字列を任意の文字で分割

	vector<string> result;
	stringstream SS(str);
	string temp;

	while (std::getline(SS, temp, key)) {
		result.push_back(temp);
	}
	return(result);
}

int main() {

	string T;
	cin >> T;

	vector<string> A = SplitString(T, ':');

	int m = stoi(A[1]);
	int h = stoi(A[0]);

	m = m + 5;
	if (m >= 60) {
		h++;
		m = m % 60;
	}
	if (h >= 24) {
		h = h % 24;
	}

	cout << setfill('0') << right << setw(2) << h << ":";
	cout << setfill('0') << right << setw(2) << m << endl;

	return 0;

}