YES
(ignored inputs)COMMENT generated by FORT "UN & ~NFP" submitted by: Franziska Rapp
Input:
   [ a -> a,
     f(b,a) -> f(a,b),
     f(?x,a) -> b ]

Make it flat:
   [ a -> a,
     f(b,a) -> f(a,b),
     f(?x,a) -> b ]
Time: 0.000 [s]

Make it Complete (R^):
   [ f(a,b) = b,
     f(b,a) = b,
     f(?x_1,a) = f(b,a),
     f(a,b) = f(?x_1,a),
     f(b,a) = f(a,b),
     f(?x,a) = f(?x_1,a),
     f(?x,a) = b ]
Time: 0.001 [s]

The number of normal forms that must be checked: 905
Time: 0.180 [s]

Now checking all the pairs...

Time to check pairs: 0.107 [s]

The TRS has Uniqueness of Normal Forms.
Total Time: 0.288 [s]

problems/738.trs: Success(UNC)
real 0.32
user 0.30
sys 0.00