#include <bits/stdc++.h>
using namespace std;
void func(void) {
  freopen("input.c", "r", stdin);
  freopen("output.c", "w", stdout);
}
int main() {
  long long n, q, i, j = 0, temp, t, k, ans = 0, sum = 0, x, y, cnt = 0, m,
                     fg = 0, mx = 0, mx1 = 0, mn = 8000000000000000000,
                     mn1 = 8000000000000000000;
  char ch;
  cin >> n >> ch >> m;
  cin >> t;
  while (t--) {
    m++;
    if (m == 60) {
      n++;
      m = 0;
      if (n == 24) n = 0;
    }
  }
  if (n < 10) cout << 0;
  cout << n << ":";
  if (m < 10) cout << 0;
  cout << m << endl;
  return 0;
}
