Given queries
Vector < Vector < Integer > > Q = new Vector < Vector < Integer > > ( ) ; Vector < Integer > v1 = new Vector < Integer > ( ) ; Vector < Integer > v2 = new Vector < Integer > ( ) ; Vector < Integer > v3 = new Vector < Integer > ( ) ; v1 . add ( 1 ) ; v2 . add ( 2 ) ; v2 . add ( 3 ) ; v3 . add ( 1 ) ; Q . add ( v1 ) ; Q . add ( v2 ) ; Q . add ( v3 ) ;