Find the lowest of the given set of data

Hi,

i want to write a macro in excel, my requirement is :

i have two sheets (say sheet1 and sheet2)
i want to check the sheet1.cell1 to sheet2.cell1 (their are many matching rows for this condition, so i get result somthing like
result is somthing like:sheet1.cell1, sheet2.cell2, result

a, b, 111
a, b, 222
a, b, 333
a, b, 444
a, b, 555
a, b, ,666

for the 1 row of sheet1 )

waht i want is to find the highest of the result (means maximum of 111,222,333,444,555,666 and result must be like
a, b, 666 )
not in series please help,,,,,,,