Term Rewriting System R:
[X, Y, Z, X1, X2, X3, X4]
plus(s(X), plus(Y, Z)) -> plus(X, plus(s(s(Y)), Z))
plus(s(X1), plus(X2, plus(X3, X4))) -> plus(X1, plus(X3, plus(X2, X4)))

Innermost Termination of R to be shown.



   R
Dependency Pair Analysis



R contains the following Dependency Pairs:

PLUS(s(X), plus(Y, Z)) -> PLUS(X, plus(s(s(Y)), Z))
PLUS(s(X), plus(Y, Z)) -> PLUS(s(s(Y)), Z)
PLUS(s(X1), plus(X2, plus(X3, X4))) -> PLUS(X1, plus(X3, plus(X2, X4)))
PLUS(s(X1), plus(X2, plus(X3, X4))) -> PLUS(X3, plus(X2, X4))
PLUS(s(X1), plus(X2, plus(X3, X4))) -> PLUS(X2, X4)

Furthermore, R contains one SCC.


   R
DPs
       →DP Problem 1
Modular Removal of Rules


Dependency Pairs:

PLUS(s(X1), plus(X2, plus(X3, X4))) -> PLUS(X3, plus(X2, X4))
PLUS(s(X1), plus(X2, plus(X3, X4))) -> PLUS(X1, plus(X3, plus(X2, X4)))
PLUS(s(X), plus(Y, Z)) -> PLUS(s(s(Y)), Z)
PLUS(s(X), plus(Y, Z)) -> PLUS(X, plus(s(s(Y)), Z))


Rules:


plus(s(X), plus(Y, Z)) -> plus(X, plus(s(s(Y)), Z))
plus(s(X1), plus(X2, plus(X3, X4))) -> plus(X1, plus(X3, plus(X2, X4)))


Strategy:

innermost




We have the following set of usable rules:

plus(s(X), plus(Y, Z)) -> plus(X, plus(s(s(Y)), Z))
plus(s(X1), plus(X2, plus(X3, X4))) -> plus(X1, plus(X3, plus(X2, X4)))
To remove rules and DPs from this DP problem we used the following monotonic and CE-compatible order: Polynomial ordering.
Polynomial interpretation:
  POL(PLUS(x1, x2))=  1 + x1 + x2  
  POL(plus(x1, x2))=  1 + x1 + x2  
  POL(s(x1))=  x1  

We have the following set D of usable symbols: {PLUS, plus, s}
The following Dependency Pairs can be deleted as the lhs is strictly greater than the corresponding rhs:

PLUS(s(X1), plus(X2, plus(X3, X4))) -> PLUS(X3, plus(X2, X4))
PLUS(s(X), plus(Y, Z)) -> PLUS(s(s(Y)), Z)

No Rules can be deleted.

The result of this processor delivers one new DP problem.



   R
DPs
       →DP Problem 1
MRR
           →DP Problem 2
Size-Change Principle


Dependency Pairs:

PLUS(s(X1), plus(X2, plus(X3, X4))) -> PLUS(X1, plus(X3, plus(X2, X4)))
PLUS(s(X), plus(Y, Z)) -> PLUS(X, plus(s(s(Y)), Z))


Rules:


plus(s(X), plus(Y, Z)) -> plus(X, plus(s(s(Y)), Z))
plus(s(X1), plus(X2, plus(X3, X4))) -> plus(X1, plus(X3, plus(X2, X4)))


Strategy:

innermost




We number the DPs as follows:
  1. PLUS(s(X1), plus(X2, plus(X3, X4))) -> PLUS(X1, plus(X3, plus(X2, X4)))
  2. PLUS(s(X), plus(Y, Z)) -> PLUS(X, plus(s(s(Y)), Z))
and get the following Size-Change Graph(s):
{2, 1} , {2, 1}
1>1

which lead(s) to this/these maximal multigraph(s):
{2, 1} , {2, 1}
1>1

DP: empty set
Oriented Rules: none

We used the order Homeomorphic Embedding Order with Non-Strict Precedence.
trivial

with Argument Filtering System:
s(x1) -> s(x1)

We obtain no new DP problems.

Innermost Termination of R successfully shown.
Duration:
0:00 minutes