{ Petri net generated by APT for net exercise 5.3 net } PLACE s1, s2, s3, s4, s5, s6, s7; MARKING s3 : 1, s5 : 1; TRANSITION t1 CONSUME s1 : 1, s2 : 1; PRODUCE s4 : 1, s3 : 1; TRANSITION t2 CONSUME s5 : 1; PRODUCE s1 : 1, s6 : 1; TRANSITION t3 CONSUME s3 : 1; PRODUCE s2 : 1, s7 : 1; TRANSITION t4 CONSUME s4 : 1, s6 : 1, s7 : 1; PRODUCE s5 : 1;