Finding similar data or numbers in two columns

[sayemasof]

I am dealing with a lot of data in spreadsheet. I need a macro program so that i can find whether there are similar data or numbers in two colums in the same worksheet.

e.g.

C1-----------C2----------C3
1256--------1125--------not present
1344--------1356--------present
1356--------1455--------not present
1526--------1256--------present

u can see that some numbers in the two column are similar. How do i sort them out and put a label beside that in the next column. I want numbers in column 2 to be checked with column1.
Can anyone help, please?

Thanks a lot