I have a quick and hopefully simple questions.

I have a source list of data (for example):

BLR1 SL1 10000
BLR2 SL2 20000
BLR3 SL3 30000
BLR4 SL1 30000

In another list, I have two input conditions in two different cells:
SL1 20000 x

I'd like a third cell where the 'x' is to tell me if I have already have
that combination in the source list. If so, indicate with a 'y'; if not;
indicate with an 'n'.

The input above would indicate an 'n', an entry of SL3, 30000 would indicate
a 'y'. The source data field may be random and not sorted in any particular
order.

Thanks.