For a point P in the plane, let $$d_1 (P)$$ and $$d_2 (P)$$ be the distances of the point P from the lines x − y = 0 and x + y = 0 respectively. The area of the region R consisting of all points P lying in the first quadrant of the plane and satisfying $$2 \leq d_1 (P) + d_2 (P) \leq 4,$$ is