YES
Time: 0.007391
TRS:
 {dfib(s s x, y) -> dfib(s x, dfib(x, y))}
 DP:
  DP:
   {dfib#(s s x, y) -> dfib#(x, y),
    dfib#(s s x, y) -> dfib#(s x, dfib(x, y))}
  TRS:
  {dfib(s s x, y) -> dfib(s x, dfib(x, y))}
  EDG:
   {(dfib#(s s x, y) -> dfib#(x, y), dfib#(s s x, y) -> dfib#(s x, dfib(x, y)))
    (dfib#(s s x, y) -> dfib#(x, y), dfib#(s s x, y) -> dfib#(x, y))
    (dfib#(s s x, y) -> dfib#(s x, dfib(x, y)), dfib#(s s x, y) -> dfib#(x, y))
    (dfib#(s s x, y) -> dfib#(s x, dfib(x, y)), dfib#(s s x, y) -> dfib#(s x, dfib(x, y)))}
   STATUS:
    arrows: 0.000000
    SCCS (1):
     Scc:
      {dfib#(s s x, y) -> dfib#(x, y),
       dfib#(s s x, y) -> dfib#(s x, dfib(x, y))}
     
     SCC (2):
      Strict:
       {dfib#(s s x, y) -> dfib#(x, y),
        dfib#(s s x, y) -> dfib#(s x, dfib(x, y))}
      Weak:
      {dfib(s s x, y) -> dfib(s x, dfib(x, y))}
      POLY:
       Mode: weak, max_in=1, output_bits=-1, dnum=1, ur=true
       Interpretation:
        [dfib](x0, x1) = 1,
        
        [s](x0) = x0 + 1,
        
        [dfib#](x0, x1) = x0 + x1
       Strict:
        dfib#(s s x, y) -> dfib#(s x, dfib(x, y))
        2 + 1x + 1y >= 2 + 1x + 0y
        dfib#(s s x, y) -> dfib#(x, y)
        2 + 1x + 1y >= 0 + 1x + 1y
       Weak:
        dfib(s s x, y) -> dfib(s x, dfib(x, y))
        1 + 0x + 0y >= 1 + 0x + 0y
      SCCS (1):
       Scc:
        {dfib#(s s x, y) -> dfib#(s x, dfib(x, y))}
       
       SCC (1):
        Strict:
         {dfib#(s s x, y) -> dfib#(s x, dfib(x, y))}
        Weak:
        {dfib(s s x, y) -> dfib(s x, dfib(x, y))}
        POLY:
         Mode: weak, max_in=1, output_bits=-1, dnum=1, ur=true
         Interpretation:
          [dfib](x0, x1) = 0,
          
          [s](x0) = x0 + 1,
          
          [dfib#](x0, x1) = x0
         Strict:
          dfib#(s s x, y) -> dfib#(s x, dfib(x, y))
          2 + 1x + 0y >= 1 + 1x + 0y
         Weak:
          dfib(s s x, y) -> dfib(s x, dfib(x, y))
          0 + 0x + 0y >= 0 + 0x + 0y
        Qed