#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
#define pb push_back
#define mp make_pair
#define rep(i,n) for(int i=0;i<(n);++i)

int main(){
	cin.tie(0);
	ios::sync_with_stdio(false);
	string s;cin >> s;
	int h=(s.at(0)-'0')*10+(s.at(1)-'0'),m=(s.at(3)-'0')*10+(s.at(4)-'0');
	m+=5;
	h+=m/60;
	m%=60;
	h%=24;
	if(h<10) cout << 0 << h;
	else cout << h;
	cout << ':';
	if(m<10) cout << 0 << m << endl;
	else cout << m << endl;
}