LTS Termination Proof

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Input

Integer Transition System

Proof

1 Switch to Cooperation Termination Proof

We consider the following cutpoint-transitions:
1 8 1: arg3P + arg3P ≤ 0arg3Parg3P ≤ 0arg3 + arg3 ≤ 0arg3arg3 ≤ 0arg2P + arg2P ≤ 0arg2Parg2P ≤ 0arg2 + arg2 ≤ 0arg2arg2 ≤ 0arg1P + arg1P ≤ 0arg1Parg1P ≤ 0arg1 + arg1 ≤ 0arg1arg1 ≤ 0
2 15 2: arg3P + arg3P ≤ 0arg3Parg3P ≤ 0arg3 + arg3 ≤ 0arg3arg3 ≤ 0arg2P + arg2P ≤ 0arg2Parg2P ≤ 0arg2 + arg2 ≤ 0arg2arg2 ≤ 0arg1P + arg1P ≤ 0arg1Parg1P ≤ 0arg1 + arg1 ≤ 0arg1arg1 ≤ 0
3 22 3: arg3P + arg3P ≤ 0arg3Parg3P ≤ 0arg3 + arg3 ≤ 0arg3arg3 ≤ 0arg2P + arg2P ≤ 0arg2Parg2P ≤ 0arg2 + arg2 ≤ 0arg2arg2 ≤ 0arg1P + arg1P ≤ 0arg1Parg1P ≤ 0arg1 + arg1 ≤ 0arg1arg1 ≤ 0
and for every transition t, a duplicate t is considered.

2 Transition Removal

We remove transitions 0, 3, 4, 7 using the following ranking functions, which are bounded by −17.

4: 0
0: 0
1: 0
2: 0
3: 0
4: −5
0: −6
1: −7
2: −7
1_var_snapshot: −7
1*: −7
2_var_snapshot: −7
2*: −7
3: −10
3_var_snapshot: −10
3*: −10

3 Location Addition

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

1* 11 1: arg3P + arg3P ≤ 0arg3Parg3P ≤ 0arg3 + arg3 ≤ 0arg3arg3 ≤ 0arg2P + arg2P ≤ 0arg2Parg2P ≤ 0arg2 + arg2 ≤ 0arg2arg2 ≤ 0arg1P + arg1P ≤ 0arg1Parg1P ≤ 0arg1 + arg1 ≤ 0arg1arg1 ≤ 0

4 Location Addition

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

1 9 1_var_snapshot: arg3P + arg3P ≤ 0arg3Parg3P ≤ 0arg3 + arg3 ≤ 0arg3arg3 ≤ 0arg2P + arg2P ≤ 0arg2Parg2P ≤ 0arg2 + arg2 ≤ 0arg2arg2 ≤ 0arg1P + arg1P ≤ 0arg1Parg1P ≤ 0arg1 + arg1 ≤ 0arg1arg1 ≤ 0

5 Location Addition

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

2* 18 2: arg3P + arg3P ≤ 0arg3Parg3P ≤ 0arg3 + arg3 ≤ 0arg3arg3 ≤ 0arg2P + arg2P ≤ 0arg2Parg2P ≤ 0arg2 + arg2 ≤ 0arg2arg2 ≤ 0arg1P + arg1P ≤ 0arg1Parg1P ≤ 0arg1 + arg1 ≤ 0arg1arg1 ≤ 0

6 Location Addition

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

2 16 2_var_snapshot: arg3P + arg3P ≤ 0arg3Parg3P ≤ 0arg3 + arg3 ≤ 0arg3arg3 ≤ 0arg2P + arg2P ≤ 0arg2Parg2P ≤ 0arg2 + arg2 ≤ 0arg2arg2 ≤ 0arg1P + arg1P ≤ 0arg1Parg1P ≤ 0arg1 + arg1 ≤ 0arg1arg1 ≤ 0

7 Location Addition

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

3* 25 3: arg3P + arg3P ≤ 0arg3Parg3P ≤ 0arg3 + arg3 ≤ 0arg3arg3 ≤ 0arg2P + arg2P ≤ 0arg2Parg2P ≤ 0arg2 + arg2 ≤ 0arg2arg2 ≤ 0arg1P + arg1P ≤ 0arg1Parg1P ≤ 0arg1 + arg1 ≤ 0arg1arg1 ≤ 0

8 Location Addition

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

3 23 3_var_snapshot: arg3P + arg3P ≤ 0arg3Parg3P ≤ 0arg3 + arg3 ≤ 0arg3arg3 ≤ 0arg2P + arg2P ≤ 0arg2Parg2P ≤ 0arg2 + arg2 ≤ 0arg2arg2 ≤ 0arg1P + arg1P ≤ 0arg1Parg1P ≤ 0arg1 + arg1 ≤ 0arg1arg1 ≤ 0

9 SCC Decomposition

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

9.1 SCC Subproblem 1/2

Here we consider the SCC { 3, 3_var_snapshot, 3* }.

9.1.1 Transition Removal

We remove transition 6 using the following ranking functions, which are bounded by 2.

3: 1 + 3⋅arg1
3_var_snapshot: 3⋅arg1
3*: 2 + 3⋅arg1

9.1.2 Transition Removal

We remove transition 23 using the following ranking functions, which are bounded by −1.

3: 0
3_var_snapshot: −1
3*: 1

9.1.3 Transition Removal

We remove transition 25 using the following ranking functions, which are bounded by 0.

3: 0
3_var_snapshot: 0
3*: 1

9.1.4 Splitting Cut-Point Transitions

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

9.1.4.1 Cut-Point Subproblem 1/1

Here we consider cut-point transition 22.

9.1.4.1.1 Splitting Cut-Point Transitions

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

9.2 SCC Subproblem 2/2

Here we consider the SCC { 1, 2, 1_var_snapshot, 1*, 2_var_snapshot, 2* }.

9.2.1 Transition Removal

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

1: 1 + 3⋅arg1
2: 3⋅arg1
1_var_snapshot: 3⋅arg1
1*: 2 + 3⋅arg1
2_var_snapshot: 3⋅arg1
2*: 3⋅arg1

9.2.2 Transition Removal

We remove transition 5 using the following ranking functions, which are bounded by −298.

1: 3 − 3⋅arg1
2: 1 − arg2 − 2⋅arg3
1_var_snapshot: 3 − 3⋅arg1
1*: 4 − 3⋅arg1
2_var_snapshot: arg2 − 2⋅arg3
2*: 2 − arg2 − 2⋅arg3

9.2.3 Transition Removal

We remove transitions 9, 16, 18, 1 using the following ranking functions, which are bounded by −3.

1: 1
2: −2
1_var_snapshot: 0
1*: 2
2_var_snapshot: −3
2*: −1

9.2.4 Transition Removal

We remove transition 11 using the following ranking functions, which are bounded by −1.

1: −1
2: 0
1_var_snapshot: 0
1*: 0
2_var_snapshot: 0
2*: 0

9.2.5 Splitting Cut-Point Transitions

We consider 2 subproblems corresponding to sets of cut-point transitions as follows.

9.2.5.1 Cut-Point Subproblem 1/2

Here we consider cut-point transition 8.

9.2.5.1.1 Splitting Cut-Point Transitions

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

9.2.5.2 Cut-Point Subproblem 2/2

Here we consider cut-point transition 15.

9.2.5.2.1 Splitting Cut-Point Transitions

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

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