As with time dilation, length contraction is symmetric. If A and B are carrying meter sticks parallel to the direction of their relative motion, A will see B's stick shrink, and B will see A's stick shrink. There is no contradiction here since we cannot compare the ends of the sticks simultaneously for both observers. This symmetry has provided some interesting puzzles that start with seeming contradictions, but end up with logical resolutions. (See Problem 7.5.)
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