user=> (mapcat reverse [[3 2 1 0] [6 5 4] [9 8 7]]) (0 1 2 3 4 5 6 7 8 9)
user> (mapcat reverse [[3 2 1 0] [6 5 4] [9 8 7]]) (0 1 2 3 4 5 6 7 8 9) user>