LTS Termination Proof

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Input

Integer Transition System

Proof

1 Switch to Cooperation Termination Proof

We consider the following cutpoint-transitions:
l5 l5 l5: x1 = x1x2 = x2x3 = x3
l4 l4 l4: x1 = x1x2 = x2x3 = x3
l7 l7 l7: x1 = x1x2 = x2x3 = x3
l6 l6 l6: x1 = x1x2 = x2x3 = x3
l11 l11 l11: x1 = x1x2 = x2x3 = x3
l8 l8 l8: x1 = x1x2 = x2x3 = x3
l1 l1 l1: x1 = x1x2 = x2x3 = x3
l3 l3 l3: x1 = x1x2 = x2x3 = x3
l0 l0 l0: x1 = x1x2 = x2x3 = x3
l12 l12 l12: x1 = x1x2 = x2x3 = x3
l2 l2 l2: x1 = x1x2 = x2x3 = x3
l9 l9 l9: x1 = x1x2 = x2x3 = x3
and for every transition t, a duplicate t is considered.

2 SCC Decomposition

We consider subproblems for each of the 2 SCC(s) of the program graph.

2.1 SCC Subproblem 1/2

Here we consider the SCC { l1, l3, l0, l2 }.

2.1.1 Transition Removal

We remove transition 15 using the following ranking functions, which are bounded by 0.

l0: 5 − x1
l1: 5 − x1
l3: 4 − x1
l2: 4 − x1

2.1.2 Transition Removal

We remove transitions 1, 12 using the following ranking functions, which are bounded by 0.

l0: 0
l1: −1
l3: 1
l2: 1

2.1.3 Transition Removal

We remove transition 13 using the following ranking functions, which are bounded by 0.

l2: 5 − x2
l3: 5 − x2

2.1.4 Transition Removal

We remove transition 2 using the following ranking functions, which are bounded by 0.

l2: 0
l3: −1

2.1.5 Trivial Cooperation Program

There are no more "sharp" transitions in the cooperation program. Hence the cooperation termination is proved.

2.2 SCC Subproblem 2/2

Here we consider the SCC { l5, l4, l7, l6, l8, l9 }.

2.2.1 Transition Removal

We remove transition 10 using the following ranking functions, which are bounded by −14.

l4: −3⋅x1 + 2
l5: −3⋅x1 + 1
l7: −3⋅x1
l6: −3⋅x1
l8: −3⋅x1
l9: −3⋅x1

2.2.2 Transition Removal

We remove transition 3 using the following ranking functions, which are bounded by −1.

l4: −1
l5: −2
l7: 0
l6: 0
l8: 0
l9: 0

2.2.3 Transition Removal

We remove transition 8 using the following ranking functions, which are bounded by −15.

l7: −3⋅x2
l4: −3⋅x2 − 1
l6: −3⋅x2 + 1
l8: −3⋅x2 − 1
l9: −3⋅x2 − 1

2.2.4 Transition Removal

We remove transition 6 using the following ranking functions, which are bounded by −10.

l7: −2⋅x3 − 2
l4: −2⋅x3 − 3
l6: −2⋅x3 − 1
l8: −2⋅x3
l9: −2⋅x3 + 1

2.2.5 Transition Removal

We remove transitions 7, 4, 5, 11 using the following ranking functions, which are bounded by 0.

l7: 0
l4: −1
l6: 1
l8: 2
l9: 3

2.2.6 Trivial Cooperation Program

There are no more "sharp" transitions in the cooperation program. Hence the cooperation termination is proved.

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