What type of formula would respond to the following conditions 12 (excel
seems to only permit up to 7...is it possible to get around that?):

IF Any Cell in Column AA= A1 and Any Cell in Column AB =B1 then C1=555
IF Any Cell in Column AA= A2 and Any Cell Column AB =B1 then C1=666
IF Any Cell in Column AA= A3 and Any Cell Column AB =B1 then C1=777

IF Any Cell in Column AA= A1 and Any Cell in Column AB =B2 then C1=888
IF Any Cell in Column AA= A2 and Any Cell in Column AB =B2 then C1=999
IF Any Cell in Column AA= A3 and Any Cell Column AB =B2 then C1=000

IF Any Cell in Column AA= A1 and Any Cell in Column AB =B3 then C1=111
IF Any Cell in Column AA= A2 and Any Cell in Column AB =B3 then C1=222
IF Any Cell in Column AA= A3 and Any Cell Column AB =B3 then C1=333

IF Any Cell in Column AA= A1 and Any Cell in Column AB =B4 then C1=1212
IF Any Cell in Column AA= A2 and Any Cell in Column AB =B4 then C1=2323
IF Any Cell in Column AA= A3 and Any Cell Column AB =B4 then C1=4545

help me please?

Alex