YES
Termination Proof
Termination Proof
by ttt2 (version ttt2 1.15)
Input
The rewrite relation of the following TRS is considered.
| 
a(a(a(b(b(x0))))) | 
→ | 
b(b(b(x0))) | 
| 
b(a(a(a(b(x0))))) | 
→ | 
a(a(a(b(a(a(a(x0))))))) | 
| 
a(a(a(x0))) | 
→ | 
a(a(x0)) | 
| 
b(b(x0)) | 
→ | 
a(b(a(x0))) | 
Proof
1 Rule Removal
      Using the
      linear polynomial interpretation over the arctic semiring over the integers
| [a(x1)] | 
 =  | 
1 · 
                    x1 + 
                -∞
             | 
| [b(x1)] | 
 =  | 
3 · 
                    x1 + 
                -∞
             | 
          the
          rules
| 
a(a(a(b(b(x0))))) | 
→ | 
b(b(b(x0))) | 
| 
b(a(a(a(b(x0))))) | 
→ | 
a(a(a(b(a(a(a(x0))))))) | 
          remain.
        1.1 Dependency Pair Transformation
          The following set of initial dependency pairs has been identified.
          
| 
a#(a(a(b(b(x0))))) | 
→ | 
b#(b(b(x0))) | 
| 
b#(a(a(a(b(x0))))) | 
→ | 
a#(x0) | 
| 
b#(a(a(a(b(x0))))) | 
→ | 
a#(a(x0)) | 
| 
b#(a(a(a(b(x0))))) | 
→ | 
a#(a(a(x0))) | 
| 
b#(a(a(a(b(x0))))) | 
→ | 
b#(a(a(a(x0)))) | 
| 
b#(a(a(a(b(x0))))) | 
→ | 
a#(b(a(a(a(x0))))) | 
| 
b#(a(a(a(b(x0))))) | 
→ | 
a#(a(b(a(a(a(x0)))))) | 
| 
b#(a(a(a(b(x0))))) | 
→ | 
a#(a(a(b(a(a(a(x0))))))) | 
1.1.1 Reduction Pair Processor with Usable Rules
        Using the linear polynomial interpretation over the arctic semiring over the integers
| [a(x1)] | 
 =  | 
1 · 
                    x1 + 
                -∞
             | 
| [b#(x1)] | 
 =  | 
4 · 
                    x1 + 
                -∞
             | 
| [b(x1)] | 
 =  | 
3 · 
                    x1 + 
                -∞
             | 
| [a#(x1)] | 
 =  | 
2 · 
                    x1 + 
                -∞
             | 
            together with the usable
            rules
| 
a(a(a(b(b(x0))))) | 
→ | 
b(b(b(x0))) | 
| 
b(a(a(a(b(x0))))) | 
→ | 
a(a(a(b(a(a(a(x0))))))) | 
            (w.r.t. the implicit argument filter of the reduction pair),
          
          the
          pairs
| 
a#(a(a(b(b(x0))))) | 
→ | 
b#(b(b(x0))) | 
| 
b#(a(a(a(b(x0))))) | 
→ | 
a#(a(a(b(a(a(a(x0))))))) | 
          remain.
        1.1.1.1 Reduction Pair Processor with Usable Rules
        Using the linear polynomial interpretation over (3 x 3)-matrices with strict dimension 1 
            over the arctic semiring over the integers
| [a(x1)] | 
 =  | 
 · 
                    x1 + 
 | 
| [b#(x1)] | 
 =  | 
 · 
                    x1 + 
| 0 | 
                -∞
             | 
                -∞
             | 
 
| 
                -∞
             | 
                -∞
             | 
                -∞
             | 
 
| 
                -∞
             | 
                -∞
             | 
                -∞
             | 
 
 
 | 
| [b(x1)] | 
 =  | 
 · 
                    x1 + 
 | 
| [a#(x1)] | 
 =  | 
 · 
                    x1 + 
| 0 | 
                -∞
             | 
                -∞
             | 
 
| 
                -∞
             | 
                -∞
             | 
                -∞
             | 
 
| 
                -∞
             | 
                -∞
             | 
                -∞
             | 
 
 
 | 
            together with the usable
            rules
| 
a(a(a(b(b(x0))))) | 
→ | 
b(b(b(x0))) | 
| 
b(a(a(a(b(x0))))) | 
→ | 
a(a(a(b(a(a(a(x0))))))) | 
            (w.r.t. the implicit argument filter of the reduction pair),
          
          the
          pair
| 
a#(a(a(b(b(x0))))) | 
→ | 
b#(b(b(x0))) | 
          remains.
        1.1.1.1.1 Dependency Graph Processor
The dependency pairs are split into 0
        components.