hi all

how i replace onr colum in excel

for example if i have sheet in excel include the following data
a
a
a
a
a
b
b
a
c
c
a
d
b
c
a
f
a
f

and i have other sheet include the following

a 12
b 22
c 4
d 55
e 23
f 12


how i replace all first sheet data by the make all a cell 12 and all b cell
22 (data from sheet 2)

with out make replacement one by one