We consider the TRS containing the following rules:
a | → | b | (1) |
a | → | d | (2) |
b | → | a | (3) |
c | → | a | (4) |
c | → | b | (5) |
The underlying signature is as follows:
{a/0, b/0, d/0, c/0}To prove that the TRS is (non-)confluent, we show (non-)confluence of the following modified system:
c | → | b | (5) |
c | → | a | (4) |
b | → | a | (3) |
a | → | d | (2) |
a | → | b | (1) |
c | → | d | (6) |
b | → | d | (7) |
b | → | b | (8) |
a | → | a | (9) |
All redundant rules that were added or removed can be simulated in 2 steps .