#include using namespace std;

int main() { double a = 0; double b = 0;

cin >> a;
b = a * 10;
a = (int)a;
b = (int)b % 10;

if (a >= 0)
{
    if (b >= 5)
        cout << a+1 << endl;
    else
        cout << a << endl;
}
else
{
    if (b <= -5)
        cout << a-1 << endl;
    else
        cout << a << endl;
}
return 0;

}