LTS Termination Proof

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Input

Integer Transition System

Proof

1 Switch to Cooperation Termination Proof

We consider the following cutpoint-transitions:
0 4 0: x_0 + x_0 ≤ 0x_0x_0 ≤ 0
and for every transition t, a duplicate t is considered.

2 Transition Removal

We remove transitions 2, 3 using the following ranking functions, which are bounded by −11.

3: 0
2: 0
0: 0
1: 0
3: −4
2: −5
0: −6
1: −6
0_var_snapshot: −6
0*: −6

3 Location Addition

The following skip-transition is inserted and corresponding redirections w.r.t. the old location are performed.

0* 7 0: x_0 + x_0 ≤ 0x_0x_0 ≤ 0

4 Location Addition

The following skip-transition is inserted and corresponding redirections w.r.t. the old location are performed.

0 5 0_var_snapshot: x_0 + x_0 ≤ 0x_0x_0 ≤ 0

5 SCC Decomposition

We consider subproblems for each of the 1 SCC(s) of the program graph.

5.1 SCC Subproblem 1/1

Here we consider the SCC { 0, 1, 0_var_snapshot, 0* }.

5.1.1 Transition Removal

We remove transition 0 using the following ranking functions, which are bounded by −1.

0: 0
1: 0
0_var_snapshot: 0
0*: 0

5.1.2 Transition Removal

We remove transitions 5, 7, 1 using the following ranking functions, which are bounded by −3.

0: −2
1: 0
0_var_snapshot: −3
0*: −1

5.1.3 Splitting Cut-Point Transitions

We consider 1 subproblems corresponding to sets of cut-point transitions as follows.

5.1.3.1 Cut-Point Subproblem 1/1

Here we consider cut-point transition 4.

5.1.3.1.1 Splitting Cut-Point Transitions

There remain no cut-point transition to consider. Hence the cooperation termination is trivial.

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