YES Termination Proof

Termination Proof

by ttt2 (version ttt2 1.15)

Input

The rewrite relation of the following TRS is considered.

b(c(x0)) a(x0)
b(b(x0)) a(c(x0))
a(x0) c(b(x0))
c(c(c(x0))) b(x0)

Proof

1 Rule Removal

Using the linear polynomial interpretation over the arctic semiring over the integers
[b(x1)] = 10 · x1 + -∞
[c(x1)] = 5 · x1 + -∞
[a(x1)] = 15 · x1 + -∞
the rules
b(c(x0)) a(x0)
b(b(x0)) a(c(x0))
a(x0) c(b(x0))
remain.

1.1 Rule Removal

Using the linear polynomial interpretation over (2 x 2)-matrices with strict dimension 1 over the arctic semiring over the integers
[b(x1)] =
1 -∞
1 1
· x1 +
-∞ -∞
-∞ -∞
[c(x1)] =
0 -∞
-∞ 0
· x1 +
-∞ -∞
-∞ -∞
[a(x1)] =
1 -∞
1 1
· x1 +
-∞ -∞
-∞ -∞
the rules
b(c(x0)) a(x0)
a(x0) c(b(x0))
remain.

1.1.1 Rule Removal

Using the Knuth Bendix order with w0 = 1 and the following precedence and weight function
prec(a) = 2 weight(a) = 1
prec(b) = 3 weight(b) = 0
prec(c) = 0 weight(c) = 1
all rules could be removed.

1.1.1.1 R is empty

There are no rules in the TRS. Hence, it is terminating.