===== PascalABC.NET =====
function g(a, b: real) :=
(a * a + b * b) / (a * a + 3 * a * b + 3 * b * b + 4);
begin
var (s, t) := ReadReal2;
Print(g(1.2, -s) + g(t, s) - g(2 * s - 1, s * t))
end.
