hello firends, how are you?

i am facing a big problem in excel(excel 2007)
suppose meray 2 column hain
Column 'A' and Column 'B'
Column 'A' main merged cells hain
A1:A2
A3:A5
A6:A10
A11:A15

ab suppose meray pass column A1:A2 (merged cell) main Value "1" hai
to main chahta hoon kay column B main B1 say B2 tak value "1" aa jaye
remember Column "B" completely unmerged hai

isi tarhan A3:A5 main agar Value "2" hai to column "B" main B3:B5 tak 2 aa jaye

manually to yeh 10 ghantoon main hoga agar app kay pass 2000 raws hoon
lekin agar koi formula ho to easily ho jaye ga
plz help me i m waiting for reply