#include #include #include #include #include #include #include #include using namespace std; vector s; int main() { s.resize(6); for (int i = 0; i < 6; i++)cin >> s[i]; sort(s.begin(), s.end()); double ans = 1.0 / 4 * (s[1] + s[2] + s[3] + s[4]) + 0.0001; cout << setprecision(7) << ans << endl; return 0; }