It is mentioned in the exercise text. You should enter something as follows:
labels 0:s1; 1:s2,s3; 2:; 3:s0,s1,s2; // encode Q
labels 0:; 1:s2,s3; 2:; 3:s2; // encode Qf
init 0,1;
transitions (0,{a},,1); (0,{},,2); (1,{},,3); (3,{a},,3); (3,{},,3);
accept 2,3;
The labels define the sets of states that form the pairs (Q,Qf) of the breakpoint construction.