MAYBE

Problem:
 +(+(x,y),z) -> +(x,+(y,z))
 +(f(x),f(y)) -> f(+(x,y))
 +(f(x),+(f(y),z)) -> +(f(+(x,y)),z)

Proof:
 Complexity Transformation Processor:
  strict:
   +(+(x,y),z) -> +(x,+(y,z))
   +(f(x),f(y)) -> f(+(x,y))
   +(f(x),+(f(y),z)) -> +(f(+(x,y)),z)
  weak:
   
  Matrix Interpretation Processor:
   dimension: 1
   max_matrix:
    1
    interpretation:
     [f](x0) = x0 + 1,
     
     [+](x0, x1) = x0 + x1
    orientation:
     +(+(x,y),z) = x + y + z >= x + y + z = +(x,+(y,z))
     
     +(f(x),f(y)) = x + y + 2 >= x + y + 1 = f(+(x,y))
     
     +(f(x),+(f(y),z)) = x + y + z + 2 >= x + y + z + 1 = +(f(+(x,y)),z)
    problem:
     strict:
      +(+(x,y),z) -> +(x,+(y,z))
     weak:
      +(f(x),f(y)) -> f(+(x,y))
      +(f(x),+(f(y),z)) -> +(f(+(x,y)),z)
    Open