MAYBE
Time: 0.000919
TRS:
 {  sum 0() -> 0(),
    sum s x -> +(sum x, s x),
  +(x, 0()) -> x,
  +(x, s y) -> s +(x, y)}
 DP:
  DP:
   {  sum# s x -> sum# x,
      sum# s x -> +#(sum x, s x),
    +#(x, s y) -> +#(x, y)}
  TRS:
  {  sum 0() -> 0(),
     sum s x -> +(sum x, s x),
   +(x, 0()) -> x,
   +(x, s y) -> s +(x, y)}
  EDG:
   {(+#(x, s y) -> +#(x, y), +#(x, s y) -> +#(x, y))
    (sum# s x -> +#(sum x, s x), +#(x, s y) -> +#(x, y))
    (sum# s x -> sum# x, sum# s x -> sum# x)
    (sum# s x -> sum# x, sum# s x -> +#(sum x, s x))}
   STATUS:
    arrows: 0.555556
    SCCS (2):
     Scc:
      {sum# s x -> sum# x}
     Scc:
      {+#(x, s y) -> +#(x, y)}
     
     SCC (1):
      Strict:
       {sum# s x -> sum# x}
      Weak:
      {  sum 0() -> 0(),
         sum s x -> +(sum x, s x),
       +(x, 0()) -> x,
       +(x, s y) -> s +(x, y)}
      Open
     
     SCC (1):
      Strict:
       {+#(x, s y) -> +#(x, y)}
      Weak:
      {  sum 0() -> 0(),
         sum s x -> +(sum x, s x),
       +(x, 0()) -> x,
       +(x, s y) -> s +(x, y)}
      Open