Input TRS:
    1: minus(minus(x)) -> x
    2: minux(+(x,y)) -> +(minus(y),minus(x))
    3: +(minus(x),+(x,y)) -> y
    4: +(+(x,y),minus(y)) -> x
Number of Rules: 4
Direct POLO(Sum) ... orients all.
	I(+) = x1 + x2
	I(minus) = x1 + 1
	I(minux) = x1 + 3
Number of Rules: 0