using namespace std; int main() { double x1, x2, y1, y2, d; cin >> x1 >> y1 >> x2 >> y2; d = sqrt(pow(x2 - x1, 2) + pow(y2 - y1, 2)); cout << fixed" /> using namespace std; int main() { double x1, x2, y1, y2, d; cin >> x1 >> y1 >> x2 >> y2; d = sqrt(pow(x2 - x1, 2) + pow(y2 - y1, 2)); cout << fixed" />