there is a shared variable between the stateless transaction
and the stateful producer in Fig. 6, and path3 reads the variable
twice. The producer writes twice during the first instance, and three
times during the second instance. pc3 is a function of r1 and r2.
If path3 is feasible, pc3 must be satisfiable when r1 is wi and r2
reads from wj (i j). Hence, after the path exploration, each