Consider two lines `L_1a n dL_2` given by `x-y=0` and `x+y=0` , respectively, and a moving point `P(x , y)dot` Let `d(P , L_1),i=1,2,` represents the distance of point `P` from the line `L_idot` If point `P` moves in a certain region `R` in such a way that `2lt=d(P , P_1)+d(P , L_1)lt=4` , find the area of region `Rdot`