Input TRS:
    1: i(0()) -> 0()
    2: +(0(),y) -> y
    3: +(x,0()) -> x
    4: i(i(x)) -> x
    5: +(i(x),x) -> 0()
    6: +(x,i(x)) -> 0()
    7: i(+(x,y)) -> +(i(x),i(y))
    8: +(x,+(y,z)) -> +(+(x,y),z)
    9: +(+(x,i(y)),y) -> x
    10: +(+(x,y),i(y)) -> x
Number of Rules: 10
Direct POLO(mSum) ... failed.