#include "bits/stdc++.h"
using namespace std;

#define DEBUG(x) cout<<#x<<": "<<x<<endl;
#define DEBUG_VEC(v) cout<<#v<<":";for(int i=0;i<v.size();i++) cout<<" "<<v[i]; cout<<endl

typedef long long ll;
#define vi vector<int>
#define vl vector<ll>
#define vii vector< vector<int> >
#define vll vector< vector<ll> >
#define vs vector<string>
#define pii pair<int,int>
#define pis pair<int,string>
#define psi pair<string,int>
#define pll pair<ll,ll>
#define fi first
#define se second
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define rep1(i,n) for(int i=1;i<=(int)(n);i++)
#define all(c) c.begin(),c.end()
const int inf = 1000000001;
const ll INF = 2e18;
#define MOD 1000000007
#define mod 1000000009
#define pi 3.14159265358979323846
#define Sp(p) cout<<setprecision(15)<< fixed<<p<<endl;
int dx[4] = { 1,0,-1,0 }, dy[4] = { 0,1,0,-1 };
int dx2[8] = { 1,1,0,-1,-1,-1,0,1 }, dy2[8] = { 0,1,1,1,0,-1,-1,-1 };


int main() {
	int a, b;
	cin >> a >> b;
	string s;
	cin >> s;
	rep(i, 3) {
		s.erase(s.begin());
	}
	char op = s[0]; s.erase(s.begin());
	double c;
	if (s.size() <= 2) {
		c = stoi(s);
	}
	else if (s[1] == '.') {
		c = s[0] - '0' + (s[2] - '0') / 10.0;
	}
	else {
		c = 10*(s[0] - '0') + (s[1] - '0') + (s[3] - '0') / 10.0;
	}
	if (op == '-') {
		c *= -1;
	}
	c -= 9;
	b += 60 * c;
	while (b < 0) {
		b += 60;
		a--;
	}
	a += b / 60 + 24;
	b %= 60;
	a %= 24;
	printf("%02d:%02d\n", a, b);

}