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

#define int long long
#define rep(i,l,r) for(int i=(int)(l);i<(int)(r);i++)
#define all(x) (x).begin(),(x).end()
#define pb push_back
template<class T>bool chmax(T &a,T b){if(a<b){a=b;return 1;}return 0;}
template<class T>bool chmin(T &a,T b){if(a>b){a=b;return 1;}return 0;}

typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<vi> vvi;

const int inf = 1LL<<60;
const int mod = 1e9 + 7;
const double eps = 1e-9;

/*{
}*/

signed main()
{
  int a, b;
  string s;
  cin >> a >> b >> s;

  double t = stof(s.substr(3, s.size()-3));
  if(t > 0){
    int u = t; 
    t -= u;

    b += t*60;
    if(b >= 60) b -= 60, a++;
    a -= 9-u;
    if(a >= 24) a -= 24;
    if(a < 0) a += 24;
  }else{
    t = abs(t);
    int u = t; 
    t -= u;

    b -= t*60;
    if(b < 0) b += 60, a--;
    a -= 9+u;
    if(a >= 24) a -= 24;
    if(a < 0) a += 24;
  }
  
  printf("%02lld:%02lld\n", a, b);

  return 0;
}