#define  _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <algorithm>
#include <utility>
#include <functional>
#include <cstring>
#include <queue>
#include <stack>
#include <math.h>
#include <iterator>
#include <vector>
#include <string>
#include <set>
#include <math.h>
#include <iostream> 
#include <random>
#include<map>
#include <iomanip>
#include <time.h>
#include <stdlib.h>
#include <list>
#include <typeinfo>
#include <list>
#include <set>
using namespace std;
#define eps 0.000000001
#define LONG_INF 10000000000000000
#define GOLD 1.61803398874989484820458
#define MAX_MOD 1000000007
#define REP(i,n) for(long long i = 0;i < n;++i)
int main() {
	string s;
	cin >> s;
	int hoge = 0;
	string a, b;
	for (int i = 3;i < 5;++i) {
		a.push_back(s[i-3] );
		b.push_back(s[i]);
	}
	hoge = stoi(a) * 60 + stoi(b);
	hoge += 5;
	hoge %= 1440;
	int nya = hoge/60;
	if (nya < 10) cout << "0";
	cout << nya;
	cout << ":";
	nya = hoge % 60;
	if (nya < 10) cout << "0";
	cout << nya;
	return 0;
}