X Y Unique ID (this is what I want)?
11 18 1
11 37 4
11 45 5
11 18 1
11 48 6
11 50 7
11 51 8
11 54 9
11 57 2
11 57 2
11 57 2
18 11 3
18 11 3

Dear, statalist community, please help. This a kind request.

Moreover, I used "egen group" but it is not helpful for my purpose .

regards, Ajay