The ornamental design for a rug, as shown and described.
FIG. 1 is an environmental perspective view of a first embodiment of a rug showing my new design;
FIG. 2 is a top plan view thereof;
FIG. 3 is a bottom plan view thereof;
FIG. 4 is an environmental perspective view of a second embodiment of a rug showing my new design;
FIG. 5 is a top plan view thereof;
FIG. 6 is a bottom plan view thereof; and,
FIG. 7 is a bottom plan view showing the sections separated.
The broken line showing of the bed in FIGS. 1 and 4 is for illustrative purposes only and forms no part of the claimed design. The broken line showing of the extension portion in FIG. 7 is for illustrative purposes only, merely showing that extensions can be used, and forms no part of the claimed design.