R
Randy Howard
Take a look at the page counts. Later editions of K&R2 are
printed on thicker paper to make it look bigger.
My two copies look almost the same, except for K&R1 is a very early
paperback edition, and K&R2 is the now *apparently* out of print
hardback version, making it a bit thicker visually from the spine,
but the pages seem to occupy about the same amount of space.