#include #include #include #include #include #include #include #include #include static const int MOD = 1000000007; using ll = long long; using u32 = unsigned; using u64 = unsigned long long; using namespace std; template constexpr T INF = ::numeric_limits::max()/32*15+208; int main() { double a, b, c, d, e, f; cin >> a >> b >> c >> d >> e >> f; e = f-e; printf("%.15lf\n", sqrt(e+c*c/4/a+d*d/4/b)); return 0; }