```    G4 Prover
Result of the test for sequent p\/q <--> q\/p

G4 Prover: a Prolog Prover for Roy Dyckhoff's Sequent Calculus G4
This prover is a fork made by Joseph Vidal-Rosset (joseph.vidal-rosset@gmail.com),
from seqprover.pl, the sequent prover for CL-X, written by Naoyuki Tamura (tamura@kobe-u.ac.jp).
Type "help." if you need some help.
fol(g4i)> fol(g4i).
yes
fol(g4i)> output(pretty).
yes
fol(g4i)> p\/q<-->q\/p.
Trying to prove with threshold = 0
Succeed in proving p\/q --> q\/p (2 msec.)
pretty:1 =
------- Ax      ------- Ax
p --> p         q --> q
---------- R\/  ---------- R\/
p --> q\/p      q --> q\/p
-------------------------- L\/
p\/q --> q\/p
Trying to prove with threshold = 0
Succeed in proving q\/p --> p\/q (2 msec.)
pretty:2 =
------- Ax      ------- Ax
q --> q         p --> p
---------- R\/  ---------- R\/
q --> p\/q      p --> p\/q
-------------------------- L\/
q\/p --> p\/q
yes
fol(g4i)> quit.
yes
Exit from Sequent Calculus Prover...
Total CPU time = 6 msec.
true

Back to g4-prover
Maintained by  Joseph Vidal-Rosset
```