YES

We show the termination of the TRS R:

  f(a(),f(b(),x)) -> f(a(),f(a(),f(a(),x)))
  f(b(),f(a(),x)) -> f(b(),f(b(),f(b(),x)))

-- SCC decomposition.

Consider the dependency pair problem (P, R), where P consists of

p1: f#(a(),f(b(),x)) -> f#(a(),f(a(),f(a(),x)))
p2: f#(a(),f(b(),x)) -> f#(a(),f(a(),x))
p3: f#(a(),f(b(),x)) -> f#(a(),x)
p4: f#(b(),f(a(),x)) -> f#(b(),f(b(),f(b(),x)))
p5: f#(b(),f(a(),x)) -> f#(b(),f(b(),x))
p6: f#(b(),f(a(),x)) -> f#(b(),x)

and R consists of:

r1: f(a(),f(b(),x)) -> f(a(),f(a(),f(a(),x)))
r2: f(b(),f(a(),x)) -> f(b(),f(b(),f(b(),x)))

The estimated dependency graph contains the following SCCs:

  {p1, p2, p3}
  {p4, p5, p6}


-- Reduction pair.

Consider the dependency pair problem (P, R), where P consists of

p1: f#(a(),f(b(),x)) -> f#(a(),f(a(),f(a(),x)))
p2: f#(a(),f(b(),x)) -> f#(a(),x)
p3: f#(a(),f(b(),x)) -> f#(a(),f(a(),x))

and R consists of:

r1: f(a(),f(b(),x)) -> f(a(),f(a(),f(a(),x)))
r2: f(b(),f(a(),x)) -> f(b(),f(b(),f(b(),x)))

The set of usable rules consists of

  r1

Take the monotone reduction pair:

  weighted path order
  
    base order:
  
      max/plus interpretations on natural numbers:
      
        f#_A(x1,x2) = max{x1 + 7, x2 + 4}
        a_A = 1
        f_A(x1,x2) = max{x1 + 2, x2}
        b_A = 2
  
    precedence:
    
      b > f# = a = f
    
    partial status:
  
      pi(f#) = [1, 2]
      pi(a) = []
      pi(f) = [1, 2]
      pi(b) = []

The next rules are strictly ordered:

  p3

We remove them from the problem.

-- SCC decomposition.

Consider the dependency pair problem (P, R), where P consists of

p1: f#(a(),f(b(),x)) -> f#(a(),f(a(),f(a(),x)))
p2: f#(a(),f(b(),x)) -> f#(a(),x)

and R consists of:

r1: f(a(),f(b(),x)) -> f(a(),f(a(),f(a(),x)))
r2: f(b(),f(a(),x)) -> f(b(),f(b(),f(b(),x)))

The estimated dependency graph contains the following SCCs:

  {p1, p2}


-- Reduction pair.

Consider the dependency pair problem (P, R), where P consists of

p1: f#(a(),f(b(),x)) -> f#(a(),f(a(),f(a(),x)))
p2: f#(a(),f(b(),x)) -> f#(a(),x)

and R consists of:

r1: f(a(),f(b(),x)) -> f(a(),f(a(),f(a(),x)))
r2: f(b(),f(a(),x)) -> f(b(),f(b(),f(b(),x)))

The set of usable rules consists of

  r1

Take the reduction pair:

  weighted path order
  
    base order:
  
      max/plus interpretations on natural numbers:
      
        f#_A(x1,x2) = max{1, x1 - 4, x2}
        a_A = 3
        f_A(x1,x2) = max{2, x1, x2}
        b_A = 3
  
    precedence:
    
      b > a = f > f#
    
    partial status:
  
      pi(f#) = [2]
      pi(a) = []
      pi(f) = [1, 2]
      pi(b) = []

The next rules are strictly ordered:

  p2

We remove them from the problem.

-- SCC decomposition.

Consider the dependency pair problem (P, R), where P consists of

p1: f#(a(),f(b(),x)) -> f#(a(),f(a(),f(a(),x)))

and R consists of:

r1: f(a(),f(b(),x)) -> f(a(),f(a(),f(a(),x)))
r2: f(b(),f(a(),x)) -> f(b(),f(b(),f(b(),x)))

The estimated dependency graph contains the following SCCs:

  {p1}


-- Reduction pair.

Consider the dependency pair problem (P, R), where P consists of

p1: f#(a(),f(b(),x)) -> f#(a(),f(a(),f(a(),x)))

and R consists of:

r1: f(a(),f(b(),x)) -> f(a(),f(a(),f(a(),x)))
r2: f(b(),f(a(),x)) -> f(b(),f(b(),f(b(),x)))

The set of usable rules consists of

  r1

Take the reduction pair:

  weighted path order
  
    base order:
  
      max/plus interpretations on natural numbers:
      
        f#_A(x1,x2) = max{x1 + 5, x2 - 3}
        a_A = 2
        f_A(x1,x2) = x1 + 21
        b_A = 14
  
    precedence:
    
      f# = a = f = b
    
    partial status:
  
      pi(f#) = [1]
      pi(a) = []
      pi(f) = []
      pi(b) = []

The next rules are strictly ordered:

  p1

We remove them from the problem.  Then no dependency pair remains.

-- Reduction pair.

Consider the dependency pair problem (P, R), where P consists of

p1: f#(b(),f(a(),x)) -> f#(b(),f(b(),f(b(),x)))
p2: f#(b(),f(a(),x)) -> f#(b(),x)
p3: f#(b(),f(a(),x)) -> f#(b(),f(b(),x))

and R consists of:

r1: f(a(),f(b(),x)) -> f(a(),f(a(),f(a(),x)))
r2: f(b(),f(a(),x)) -> f(b(),f(b(),f(b(),x)))

The set of usable rules consists of

  r2

Take the monotone reduction pair:

  weighted path order
  
    base order:
  
      max/plus interpretations on natural numbers:
      
        f#_A(x1,x2) = max{x1 + 7, x2 + 4}
        b_A = 1
        f_A(x1,x2) = max{x1 + 2, x2}
        a_A = 2
  
    precedence:
    
      a > f# = b = f
    
    partial status:
  
      pi(f#) = [1, 2]
      pi(b) = []
      pi(f) = [1, 2]
      pi(a) = []

The next rules are strictly ordered:

  p3

We remove them from the problem.

-- SCC decomposition.

Consider the dependency pair problem (P, R), where P consists of

p1: f#(b(),f(a(),x)) -> f#(b(),f(b(),f(b(),x)))
p2: f#(b(),f(a(),x)) -> f#(b(),x)

and R consists of:

r1: f(a(),f(b(),x)) -> f(a(),f(a(),f(a(),x)))
r2: f(b(),f(a(),x)) -> f(b(),f(b(),f(b(),x)))

The estimated dependency graph contains the following SCCs:

  {p1, p2}


-- Reduction pair.

Consider the dependency pair problem (P, R), where P consists of

p1: f#(b(),f(a(),x)) -> f#(b(),f(b(),f(b(),x)))
p2: f#(b(),f(a(),x)) -> f#(b(),x)

and R consists of:

r1: f(a(),f(b(),x)) -> f(a(),f(a(),f(a(),x)))
r2: f(b(),f(a(),x)) -> f(b(),f(b(),f(b(),x)))

The set of usable rules consists of

  r2

Take the reduction pair:

  weighted path order
  
    base order:
  
      max/plus interpretations on natural numbers:
      
        f#_A(x1,x2) = max{1, x1 - 4, x2}
        b_A = 3
        f_A(x1,x2) = max{2, x1, x2}
        a_A = 3
  
    precedence:
    
      a > b = f > f#
    
    partial status:
  
      pi(f#) = [2]
      pi(b) = []
      pi(f) = [1, 2]
      pi(a) = []

The next rules are strictly ordered:

  p2

We remove them from the problem.

-- SCC decomposition.

Consider the dependency pair problem (P, R), where P consists of

p1: f#(b(),f(a(),x)) -> f#(b(),f(b(),f(b(),x)))

and R consists of:

r1: f(a(),f(b(),x)) -> f(a(),f(a(),f(a(),x)))
r2: f(b(),f(a(),x)) -> f(b(),f(b(),f(b(),x)))

The estimated dependency graph contains the following SCCs:

  {p1}


-- Reduction pair.

Consider the dependency pair problem (P, R), where P consists of

p1: f#(b(),f(a(),x)) -> f#(b(),f(b(),f(b(),x)))

and R consists of:

r1: f(a(),f(b(),x)) -> f(a(),f(a(),f(a(),x)))
r2: f(b(),f(a(),x)) -> f(b(),f(b(),f(b(),x)))

The set of usable rules consists of

  r2

Take the reduction pair:

  weighted path order
  
    base order:
  
      max/plus interpretations on natural numbers:
      
        f#_A(x1,x2) = max{x1 + 5, x2 - 3}
        b_A = 2
        f_A(x1,x2) = x1 + 21
        a_A = 14
  
    precedence:
    
      f# = b = f = a
    
    partial status:
  
      pi(f#) = [1]
      pi(b) = []
      pi(f) = []
      pi(a) = []

The next rules are strictly ordered:

  p1

We remove them from the problem.  Then no dependency pair remains.