TRS:
 {f(g(x)) -> g(g(f(x))),
  f(g(x)) -> g(g(g(x)))}
 POP* + Boolean Semantic Labelling:
  Normal positions:
  pi(f_sl=1) = [1], pi(f_sl=0) = [1]
  
Safe positions:
   pi(g_sl=1) = [1], pi(g_sl=0) = [1]
  
Precedence:
   f_sl=0 > g_sl=0
   empty
  
Interpretation:
   g^(1):
   0 | 0
   1 | 0
   f^(1):
   0 | 0
   1 | 0
   
  
Labelling:
   g^(1):
   0 | 0
   1 | 0
   f^(1):
   0 | 0
   1 | 0
   
  
Labelled predicative System:
   {f_sl=0(g_sl=0(;x);) -> g_sl=0(;g_sl=0(;f_sl=0(x;))),
    f_sl=0(g_sl=0(;x);) -> g_sl=0(;g_sl=0(;f_sl=0(x;))),
    f_sl=0(g_sl=0(;x);) -> g_sl=0(;g_sl=0(;g_sl=0(;x))),
    f_sl=0(g_sl=0(;x);) -> g_sl=0(;g_sl=0(;g_sl=0(;x)))}
  

  Qed