USER WHO HAS TWO ACCOUNTS

Question

Hi,

Please help me to solve it .

USERID	ACID
100	1
100	2
100	3
100	4
101	2
102	1
103	2
103	3
103	4

I need who has accounts both 2 and 3 .

 

OUTPUT

 

OUTPUT
100	2
100	3
103	2
103	3