MAYBE
Time: 0.019260
TRS:
 {  double x -> +(x, x),
  double 0() -> 0(),
  double s x -> s s double x,
   +(x, 0()) -> x,
   +(x, s y) -> s +(x, y),
   +(s x, y) -> s +(x, y)}
 DP:
  DP:
   {  double# x -> +#(x, x),
    double# s x -> double# x,
     +#(x, s y) -> +#(x, y),
     +#(s x, y) -> +#(x, y)}
  TRS:
  {  double x -> +(x, x),
   double 0() -> 0(),
   double s x -> s s double x,
    +(x, 0()) -> x,
    +(x, s y) -> s +(x, y),
    +(s x, y) -> s +(x, y)}
  UR:
   {a(z, w) -> z,
    a(z, w) -> w}
   EDG:
    {(+#(x, s y) -> +#(x, y), +#(s x, y) -> +#(x, y))
     (+#(x, s y) -> +#(x, y), +#(x, s y) -> +#(x, y))
     (double# x -> +#(x, x), +#(s x, y) -> +#(x, y))
     (double# x -> +#(x, x), +#(x, s y) -> +#(x, y))
     (+#(s x, y) -> +#(x, y), +#(x, s y) -> +#(x, y))
     (+#(s x, y) -> +#(x, y), +#(s x, y) -> +#(x, y))
     (double# s x -> double# x, double# x -> +#(x, x))
     (double# s x -> double# x, double# s x -> double# x)}
    STATUS:
     arrows: 0.500000
     SCCS (2):
      Scc:
       {double# s x -> double# x}
      Scc:
       {+#(x, s y) -> +#(x, y),
        +#(s x, y) -> +#(x, y)}
      
      SCC (1):
       Strict:
        {double# s x -> double# x}
       Weak:
       {  double x -> +(x, x),
        double 0() -> 0(),
        double s x -> s s double x,
         +(x, 0()) -> x,
         +(x, s y) -> s +(x, y),
         +(s x, y) -> s +(x, y)}
       Open
      
      SCC (2):
       Strict:
        {+#(x, s y) -> +#(x, y),
         +#(s x, y) -> +#(x, y)}
       Weak:
       {  double x -> +(x, x),
        double 0() -> 0(),
        double s x -> s s double x,
         +(x, 0()) -> x,
         +(x, s y) -> s +(x, y),
         +(s x, y) -> s +(x, y)}
       Open