If statement - does value in cell "a" occur anywhere in column "b".

Sorry the title isn't clearer.

I've got two lists - (text, but could be converted to number if easier - they're course codes which start with letter, but I could drop that)

I need to take each value from the longer list (c. 900 items) & see if it occurs anywhere in the shorter list (c. 600 items) & to return a 1/0.

It struck me that I should be using some form of nested "if" statement, but the actual logic required is a bit beyond me.

Most of the functions seem to require an array to match against - and as far as I can see, I have to enter that array, I can't use a column to form it.

I did try VLOOKUP - but that seemed to want me to return a value that it found in a different column - so I added a column of 1s ...

but I'm clearly doing something wrong!

At the moment, the two columns of numbers are on different sheets.

I've got Office 2007 here, but have 2003 at home, if it works better in that.