(VAR x y z )
(RULES 
        c(0, x) -> x
        c(x, c(y, z)) -> c(+(x, y), z)
        +(0, 0) -> 0
        +(0, 1) -> 1
        +(0, 2) -> 2
        +(0, 3) -> 3
        +(0, 4) -> 4
        +(0, 5) -> 5
        +(0, 6) -> 6
        +(0, 7) -> 7
        +(0, 8) -> 8
        +(0, 9) -> 9
        +(1, 0) -> 1
        +(1, 1) -> 2
        +(1, 2) -> 3
        +(1, 3) -> 4
        +(1, 4) -> 5
        +(1, 5) -> 6
        +(1, 6) -> 7
        +(1, 7) -> 8
        +(1, 8) -> 9
        +(1, 9) -> c(1, 0)
        +(2, 0) -> 2
        +(2, 1) -> 3
        +(2, 2) -> 4
        +(2, 3) -> 5
        +(2, 4) -> 6
        +(2, 5) -> 7
        +(2, 6) -> 8
        +(2, 7) -> 9
        +(2, 8) -> c(1, 0)
        +(2, 9) -> c(1, 1)
        +(3, 0) -> 3
        +(3, 1) -> 4
        +(3, 2) -> 5
        +(3, 3) -> 6
        +(3, 4) -> 7
        +(3, 5) -> 8
        +(3, 6) -> 9
        +(3, 7) -> c(1, 0)
        +(3, 8) -> c(1, 1)
        +(3, 9) -> c(1, 2)
        +(4, 0) -> 4
        +(4, 1) -> 5
        +(4, 2) -> 6
        +(4, 3) -> 7
        +(4, 4) -> 8
        +(4, 5) -> 9
        +(4, 6) -> c(1, 0)
        +(4, 7) -> c(1, 1)
        +(4, 8) -> c(1, 2)
        +(4, 9) -> c(1, 3)
        +(5, 0) -> 5
        +(5, 1) -> 6
        +(5, 2) -> 7
        +(5, 3) -> 8
        +(5, 4) -> 9
        +(5, 5) -> c(1, 0)
        +(5, 6) -> c(1, 1)
        +(5, 7) -> c(1, 2)
        +(5, 8) -> c(1, 3)
        +(5, 9) -> c(1, 4)
        +(6, 0) -> 6
        +(6, 1) -> 7
        +(6, 2) -> 8
        +(6, 3) -> 9
        +(6, 4) -> c(1, 0)
        +(6, 5) -> c(1, 1)
        +(6, 6) -> c(1, 2)
        +(6, 7) -> c(1, 3)
        +(6, 8) -> c(1, 4)
        +(6, 9) -> c(1, 5)
        +(7, 0) -> 7
        +(7, 1) -> 8
        +(7, 2) -> 9
        +(7, 3) -> c(1, 0)
        +(7, 4) -> c(1, 1)
        +(7, 5) -> c(1, 2)
        +(7, 6) -> c(1, 3)
        +(7, 7) -> c(1, 4)
        +(7, 8) -> c(1, 5)
        +(7, 9) -> c(1, 6)
        +(8, 0) -> 8
        +(8, 1) -> 9
        +(8, 2) -> c(1, 0)
        +(8, 3) -> c(1, 1)
        +(8, 4) -> c(1, 2)
        +(8, 5) -> c(1, 3)
        +(8, 6) -> c(1, 4)
        +(8, 7) -> c(1, 5)
        +(8, 8) -> c(1, 6)
        +(8, 9) -> c(1, 7)
        +(9, 0) -> 9
        +(9, 1) -> c(1, 0)
        +(9, 2) -> c(1, 1)
        +(9, 3) -> c(1, 2)
        +(9, 4) -> c(1, 3)
        +(9, 5) -> c(1, 4)
        +(9, 6) -> c(1, 5)
        +(9, 7) -> c(1, 6)
        +(9, 8) -> c(1, 7)
        +(9, 9) -> c(1, 8)
        +(x, c(y, z)) -> c(y, +(x, z))
        +(c(x, y), z) -> c(x, +(y, z))
        *(0, 0) -> 0
        *(0, 1) -> 0
        *(0, 2) -> 0
        *(0, 3) -> 0
        *(0, 4) -> 0
        *(0, 5) -> 0
        *(0, 6) -> 0
        *(0, 7) -> 0
        *(0, 8) -> 0
        *(0, 9) -> 0
        *(1, 0) -> 0
        *(1, 1) -> 1
        *(1, 2) -> 2
        *(1, 3) -> 3
        *(1, 4) -> 4
        *(1, 5) -> 5
        *(1, 6) -> 6
        *(1, 7) -> 7
        *(1, 8) -> 8
        *(1, 9) -> 9
        *(2, 0) -> 0
        *(2, 1) -> 2
        *(2, 2) -> 4
        *(2, 3) -> 6
        *(2, 4) -> 8
        *(2, 5) -> c(1, 0)
        *(2, 6) -> c(1, 2)
        *(2, 7) -> c(1, 4)
        *(2, 8) -> c(1, 6)
        *(2, 9) -> c(1, 8)
        *(3, 0) -> 0
        *(3, 1) -> 3
        *(3, 2) -> 6
        *(3, 3) -> 9
        *(3, 4) -> c(1, 2)
        *(3, 5) -> c(1, 5)
        *(3, 6) -> c(1, 8)
        *(3, 7) -> c(2, 1)
        *(3, 8) -> c(2, 4)
        *(3, 9) -> c(2, 7)
        *(4, 0) -> 0
        *(4, 1) -> 4
        *(4, 2) -> 8
        *(4, 3) -> c(1, 2)
        *(4, 4) -> c(1, 6)
        *(4, 5) -> c(2, 0)
        *(4, 6) -> c(2, 4)
        *(4, 7) -> c(2, 8)
        *(4, 8) -> c(3, 2)
        *(4, 9) -> c(3, 6)
        *(5, 0) -> 0
        *(5, 1) -> 5
        *(5, 2) -> c(1, 0)
        *(5, 3) -> c(1, 5)
        *(5, 4) -> c(2, 0)
        *(5, 5) -> c(2, 5)
        *(5, 6) -> c(3, 0)
        *(5, 7) -> c(3, 5)
        *(5, 8) -> c(4, 0)
        *(5, 9) -> c(4, 5)
        *(6, 0) -> 0
        *(6, 1) -> 6
        *(6, 2) -> c(1, 2)
        *(6, 3) -> c(1, 8)
        *(6, 4) -> c(2, 4)
        *(6, 5) -> c(3, 0)
        *(6, 6) -> c(3, 6)
        *(6, 7) -> c(4, 2)
        *(6, 8) -> c(4, 8)
        *(6, 9) -> c(5, 4)
        *(7, 0) -> 0
        *(7, 1) -> 7
        *(7, 2) -> c(1, 4)
        *(7, 3) -> c(2, 1)
        *(7, 4) -> c(2, 8)
        *(7, 5) -> c(3, 5)
        *(7, 6) -> c(4, 2)
        *(7, 7) -> c(4, 9)
        *(7, 8) -> c(5, 6)
        *(7, 9) -> c(6, 3)
        *(8, 0) -> 0
        *(8, 1) -> 8
        *(8, 2) -> c(1, 8)
        *(8, 3) -> c(2, 4)
        *(8, 4) -> c(3, 2)
        *(8, 5) -> c(4, 0)
        *(8, 6) -> c(4, 8)
        *(8, 7) -> c(5, 6)
        *(8, 8) -> c(6, 4)
        *(8, 9) -> c(7, 2)
        *(9, 0) -> 0
        *(9, 1) -> 9
        *(9, 2) -> c(1, 8)
        *(9, 3) -> c(2, 7)
        *(9, 4) -> c(3, 6)
        *(9, 5) -> c(4, 5)
        *(9, 6) -> c(5, 4)
        *(9, 7) -> c(6, 3)
        *(9, 8) -> c(7, 2)
        *(9, 9) -> c(8, 1)
        *(x, c(y, z)) -> c(*(x, y), *(x, z))
        *(c(x, y), z) -> c(*(x, z), *(y, z))
        
)