X = {x0,x1}
Var x0 has 2 states (possible values).
Var x1 has 3 states.
VarSet {x0,x1} has 6 states (joint assignments of its variables).
States of VarSets correspond to states of their constituent Vars:
state of x0: state of x1: state of X:
0 0 0
1 0 1
0 1 2
1 1 3
0 2 4
1 2 5
And vice versa:
state of x0: state of x1: state of X:
0 0 0
1 0 1
0 1 2
1 1 3
0 2 4
1 2 5