YES
Input TRS:
      1: a__U11(tt(),M,N) -> a__U12(tt(),M,N)
      2: a__U12(tt(),M,N) -> s(a__plus(mark(N),mark(M)))
      3: a__plus(N,0()) -> mark(N)
      4: a__plus(N,s(M)) -> a__U11(tt(),M,N)
      5: mark(U11(X1,X2,X3)) -> a__U11(mark(X1),X2,X3)
      6: mark(U12(X1,X2,X3)) -> a__U12(mark(X1),X2,X3)
      7: mark(plus(X1,X2)) -> a__plus(mark(X1),mark(X2))
      8: mark(tt()) -> tt()
      9: mark(s(X)) -> s(mark(X))
      10: mark(0()) -> 0()
      11: a__U11(X1,X2,X3) -> U11(X1,X2,X3)
      12: a__U12(X1,X2,X3) -> U12(X1,X2,X3)
      13: a__plus(X1,X2) -> plus(X1,X2)
Number of strict rules: 13
Direct POLO(bPol) ... removes: 3
      a__plus	w: x1 + x2 + 1
      U11	w: x1 + x2 + x3 + 3
      s 	w: x1 + 3
      U12	w: x1 + x2 + x3 + 3
      0 	w: 1
      mark	w: x1
      a__U11	w: x1 + x2 + x3 + 3
      a__U12	w: x1 + x2 + x3 + 3
      plus	w: x1 + x2 + 1
      tt	w: 1
Number of strict rules: 12
Direct POLO(bPol) ... removes: 4 1 2
      a__plus	w: x1 + 2 * x2 + 3
      U11	w: x1 + 2 * x2 + x3 + 7
      s 	w: x1 + 3
      U12	w: x1 + 2 * x2 + x3 + 6
      0 	w: 7177
      mark	w: x1
      a__U11	w: x1 + 2 * x2 + x3 + 7
      a__U12	w: x1 + 2 * x2 + x3 + 6
      plus	w: x1 + 2 * x2 + 3
      tt	w: 1
Number of strict rules: 9
Direct POLO(bPol) ... failed.
Uncurrying ... failed.
Dependency Pairs:
     #1: #mark(U12(X1,X2,X3)) -> #a__U12(mark(X1),X2,X3)
     #2: #mark(U12(X1,X2,X3)) -> #mark(X1)
     #3: #mark(s(X)) -> #mark(X)
     #4: #mark(plus(X1,X2)) -> #a__plus(mark(X1),mark(X2))
     #5: #mark(plus(X1,X2)) -> #mark(X1)
     #6: #mark(plus(X1,X2)) -> #mark(X2)
     #7: #mark(U11(X1,X2,X3)) -> #a__U11(mark(X1),X2,X3)
     #8: #mark(U11(X1,X2,X3)) -> #mark(X1)
Number of SCCs: 1, DPs: 5
  SCC { #2 #3 #5 #6 #8 }
POLO(Sum)... succeeded.
      a__plus	w: 0
      U11	w: x1 + 1
      s 	w: x1 + 1
      #a__U11	w: 0
      U12	w: x1 + 1
      #a__U12	w: 0
      #a__plus	w: 0
      #mark	w: x1
      0 	w: 0
      mark	w: 0
      a__U11	w: 0
      a__U12	w: 0
      plus	w: x1 + x2 + 1
      tt	w: 0
    USABLE RULES: { }
    Removed DPs: #2 #3 #5 #6 #8
Number of SCCs: 0, DPs: 0