13. As shown in the figure, five identical small squares numbered 1-5 are placed inside the isosceles right triangle $\mathrm{ABC}$. The sum of the areas of these five small squares is 2014. Let the area of the shaded quadrilateral BDEF be $S$, then $S=$ $\qquad$ .
【Answer】2014
Analysis: The entire figure can be divided into 12.5 small squares.
The area to be found is the large triangle minus the rest, the rest $\mathrm{S}_{\triangle \mathrm{ABD}}$ and $\mathrm{S}_{\mathrm{CDGF}}$ are 7.5 small squares, so the required area is 5 small squares, and the area of 5 small squares is exactly 2014.