I wonder how many responses fail the assignment for making assumptions like this (that 'numbers' means 'integers'). $ cat file 1 1.2 3 4.5

I wonder how many responses fail the assignment for making assumptions like this (that 'numbers' means 'integers'). $ cat file 1 1.2 3 4.5 $ egrep --only-matching '^[0-9]+' file 1 1 3 Surely still demonstrates ability, but an automated testing suite is going to throw it out.