#include "bits/stdc++.h"

#define rep(a,b) for(int a = 0;a < b;a++)
#define REP(i, x, n) for(int i = x; i < n; i++)
#define P(a) cout << a << endl
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
int dx[] = { 1, -1 , 0 , 0 };
int dy[] = { 0,  0,  1, -1 };
unsigned long long str_to_int(std::string str) {
	unsigned long long ret;
	std::stringstream ss; ss << str;
	ss >> ret;
	return ret;
}

int main() {
	string s;
	cin >> s;
	int h = (s[0] - '0') * 10 + (s[1] - '0');
	int m = (s[3] - '0') * 10 + (s[4] - '0');
	m += 5;
	if(m >= 60){
		m %= 60;
		h += 1;
		h %= 24;
	}
	string ans = "";
	if (h <= 9) {
		ans = ans + '0' + to_string(h) + ':';
	}
	else {
		ans = ans + to_string(h) + ':';
	}
	if (m <= 9) {
		ans = ans + '0' + to_string(m);
	}
	else {
		ans = ans + to_string(m);
	}
	P(ans);
}