Higher_Order_Rewriting_Union_Beta 2019-03-28 22.10 pair #432270473

details

property	value
status	complete
benchmark	h55.xml
ran by	Akihisa Yamada
cpu timeout	1200 seconds
wallclock timeout	300 seconds
memory limit	137438953472 bytes
execution host	n062.star.cs.uiowa.edu
space	Hamana_Kikuchi_18

run statistics

property	value
solver	Wanda 2.1c
configuration	default
runtime (wallclock)	0.106921 seconds
cpu usage	0.107162
user time	0.082603
system time	0.024559
max virtual memory	113176.0
max residence set size	5072.0

stage attributes

key	value
starexec-result	YES

output

0.00/0.09	YES
0.00/0.10	We consider the system theBenchmark.
0.00/0.10	
0.00/0.10	  Alphabet:
0.00/0.10	
0.00/0.10	    cons : [] --> a -> b -> b 
0.00/0.10	    foldr : [] --> (a -> b -> b) -> b -> b -> b 
0.00/0.10	    nil : [] --> b 
0.00/0.10	
0.00/0.10	  Rules:
0.00/0.10	
0.00/0.10	    foldr (/\x./\y.f x y) z nil => z 
0.00/0.10	    foldr (/\x./\y.f x y) z (cons u v) => f u (foldr (/\w./\x'.f w x') z v) 
0.00/0.10	
0.00/0.10	Using the transformations described in [Kop11], this system can be brought in a form without leading free variables in the left-hand side, and where the left-hand side of a variable is always a functional term or application headed by a functional term.
0.00/0.10	
0.00/0.10	We now transform the resulting AFS into an AFSM by replacing all free variables by meta-variables (with arity 0).  This leads to the following AFSM:
0.00/0.10	
0.00/0.10	  Alphabet:
0.00/0.10	
0.00/0.10	    cons : [a * b] --> b 
0.00/0.10	    foldr : [a -> b -> b * b * b] --> b 
0.00/0.10	    nil : [] --> b 
0.00/0.10	    ~AP1 : [a -> b -> b * a] --> b -> b 
0.00/0.10	
0.00/0.10	  Rules:
0.00/0.10	
0.00/0.10	    foldr(/\x./\y.~AP1(F, x) y, X, nil) => X 
0.00/0.10	    foldr(/\x./\y.~AP1(F, x) y, X, cons(Y, Z)) => ~AP1(F, Y) foldr(/\z./\u.~AP1(F, z) u, X, Z) 
0.00/0.10	    foldr(/\x./\y.cons(x, y), X, nil) => X 
0.00/0.10	    foldr(/\x./\y.cons(x, y), X, cons(Y, Z)) => cons(Y, foldr(/\z./\u.cons(z, u), X, Z)) 
0.00/0.10	    ~AP1(F, X) => F X 
0.00/0.10	
0.00/0.10	Symbol ~AP1 is an encoding for application that is only used in innocuous ways.  We can simplify the program (without losing non-termination) by removing it.  Additionally, we can remove some (now-)redundant rules.  This gives:
0.00/0.10	
0.00/0.10	  Alphabet:
0.00/0.10	
0.00/0.10	    cons : [a * b] --> b 
0.00/0.10	    foldr : [a -> b -> b * b * b] --> b 
0.00/0.10	    nil : [] --> b 
0.00/0.10	
0.00/0.10	  Rules:
0.00/0.10	
0.00/0.10	    foldr(/\x./\y.X(x, y), Y, nil) => Y 
0.00/0.10	    foldr(/\x./\y.X(x, y), Y, cons(Z, U)) => X(Z, foldr(/\z./\u.X(z, u), Y, U)) 
0.00/0.10	
0.00/0.10	We use rule removal, following [Kop12, Theorem 2.23].
0.00/0.10	
0.00/0.10	This gives the following requirements (possibly using Theorems 2.25 and 2.26 in [Kop12]):
0.00/0.10	
0.00/0.10	  foldr(/\x./\y.X(x, y), Y, nil) >? Y 
0.00/0.10	  foldr(/\x./\y.X(x, y), Y, cons(Z, U)) >? X(Z, foldr(/\z./\u.X(z, u), Y, U)) 
0.00/0.10	
0.00/0.10	We use a recursive path ordering as defined in [Kop12, Chapter 5].
0.00/0.10	
0.00/0.10	We choose Lex = {} and Mul = {cons, foldr, nil}, and the following precedence: cons > foldr > nil
0.00/0.10	
0.00/0.10	With these choices, we have:
0.00/0.10	
0.00/0.10	  1] foldr(/\x./\y.X(x, y), Y, nil) >= Y  because [2], by (Star) 
0.00/0.10	  2] foldr*(/\x./\y.X(x, y), Y, nil) >= Y  because [3], by (Select) 
0.00/0.10	  3] Y >= Y  by (Meta) 
0.00/0.10	
0.00/0.10	  4] foldr(/\x./\y.X(x, y), Y, cons(Z, U)) > X(Z, foldr(/\x./\y.X(x, y), Y, U))  because [5], by definition 
0.00/0.10	  5] foldr*(/\x./\y.X(x, y), Y, cons(Z, U)) >= X(Z, foldr(/\x./\y.X(x, y), Y, U))  because [6], by (Select) 
0.00/0.10	  6] X(foldr*(/\x./\y.X(x, y), Y, cons(Z, U)), foldr*(/\z./\u.X(z, u), Y, cons(Z, U))) >= X(Z, foldr(/\x./\y.X(x, y), Y, U))  because [7] and [11], by (Meta) 
0.00/0.10	  7] foldr*(/\x./\y.X(x, y), Y, cons(Z, U)) >= Z  because [8], by (Select) 
0.00/0.10	  8] cons(Z, U) >= Z  because [9], by (Star) 
0.00/0.10	  9] cons*(Z, U) >= Z  because [10], by (Select) 
0.00/0.10	  10] Z >= Z  by (Meta) 
0.00/0.10	  11] foldr*(/\x./\y.X(x, y), Y, cons(Z, U)) >= foldr(/\x./\y.X(x, y), Y, U)  because foldr in Mul, [12], [17] and [18], by (Stat) 
0.00/0.10	  12] /\x./\z.X(x, z) >= /\x./\z.X(x, z)  because [13], by (Abs) 
0.00/0.10	  13] /\z.X(y, z) >= /\z.X(y, z)  because [14], by (Abs) 
0.00/0.10	  14] X(y, x) >= X(y, x)  because [15] and [16], by (Meta) 
0.00/0.10	  15] y >= y  by (Var) 
0.00/0.10	  16] x >= x  by (Var) 
0.00/0.10	  17] Y >= Y  by (Meta) 
0.00/0.10	  18] cons(Z, U) > U  because [19], by definition 
0.00/0.10	  19] cons*(Z, U) >= U  because [20], by (Select) 
0.00/0.10	  20] U >= U  by (Meta) 
0.00/0.10	
0.00/0.10	We can thus remove the following rules:
0.00/0.10	
0.00/0.10	  foldr(/\x./\y.X(x, y), Y, cons(Z, U)) => X(Z, foldr(/\z./\u.X(z, u), Y, U)) 
0.00/0.10	
0.00/0.10	We use rule removal, following [Kop12, Theorem 2.23].
0.00/0.10	
0.00/0.10	This gives the following requirements (possibly using Theorems 2.25 and 2.26 in [Kop12]):
0.00/0.10	
0.00/0.10	  foldr(/\x./\y.X(x, y), Y, nil) >? Y 
0.00/0.10	
0.00/0.10	We orient these requirements with a polynomial interpretation in the natural numbers.
0.00/0.10	
0.00/0.10	The following interpretation satisfies the requirements:
0.00/0.10	
0.00/0.10	  foldr = \G0y1y2.3 + y1 + y2 + G0(0,0) 
0.00/0.10	  nil = 3 
0.00/0.10	
0.00/0.10	Using this interpretation, the requirements translate to:
0.00/0.10

popout

output may be truncated. 'popout' for the full output.

job log

popout

actions all output return to Higher_Order_Rewriting_Union_Beta 2019-03-28 22.10