(GOAL COMPLEXITY)
(STARTTERM (FUNCTIONSYMBOLS l0))
(VAR A B F X)
(RULES
  l0(A,B,F,X) -> Com_1(l1(A,B,F,X))
  l1(A,B,F,X) -> Com_1(l1(A,B,F + X,X - 1)) :|: X >= 1
  l1(A,B,F,X) -> Com_1(l2(A,B,F,X)) :|: X < 1
  l2(A,B,F,X) -> Com_1(l3(F,F,F,X)) :|: F >= 1
  l3(A,B,F,X) -> Com_1(l3(A + B,B - 1,F,X)) :|: A >= 1
  l3(A,B,F,X) -> Com_1(l2(A,B,F - 1,X)) :|: 0 >= A
)