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Diffstat (limited to 'test-suite/bugs/closed/1414.v')
-rw-r--r-- | test-suite/bugs/closed/1414.v | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/test-suite/bugs/closed/1414.v b/test-suite/bugs/closed/1414.v new file mode 100644 index 00000000..ee9e2504 --- /dev/null +++ b/test-suite/bugs/closed/1414.v @@ -0,0 +1,40 @@ +Require Import ZArith Coq.Program.Wf Coq.Program.Utils. + +Parameter data:Set. + +Inductive t : Set := + | Leaf : t + | Node : t -> data -> t -> Z -> t. + +Parameter avl : t -> Prop. +Parameter bst : t -> Prop. +Parameter In : data -> t -> Prop. +Parameter cardinal : t -> nat. +Definition card2 (s:t*t) := let (s1,s2) := s in cardinal s1 + cardinal s2. + +Parameter split : data -> t -> t*(bool*t). +Parameter join : t -> data -> t -> t. +Parameter add : data -> t -> t. + +Program Fixpoint union + (s u:t) + (hb1: bst s)(ha1: avl s)(hb2: bst u)(hb2: avl u) + { measure (cardinal s + cardinal u) } : + {s' : t | bst s' /\ avl s' /\ forall x, In x s' <-> In x s \/ In x u} := + match s, u with + | Leaf,t2 => t2 + | t1,Leaf => t1 + | Node l1 v1 r1 h1, Node l2 v2 r2 h2 => + if (Z_ge_lt_dec h1 h2) then + if (Z.eq_dec h2 1) + then add v2 s + else + let (l2', r2') := split v1 u in + join (union l1 l2' _ _ _ _) v1 (union r1 (snd r2') _ _ _ _) + else + if (Z.eq_dec h1 1) + then add v1 s + else + let (l1', r1') := split v2 u in + join (union l1' l2 _ _ _ _) v2 (union (snd r1') r2 _ _ _ _) + end. |