-- Mathlib/Data/Ordmap/Ordset.lean
theorem Valid'.rotateL {l} {x : α} {r o₁ o₂} (hl : Valid' o₁ l x) (hr : Valid' x r o₂)
    (H1 : ¬size l + size r ≤ 1) (H2 : delta * size l < size r)
    (H3 : 2 * size r ≤ 9 * size l + 5 ∨ size r ≤ 3) : Valid' o₁ (@rotateL α l x r) o₂

Proof state:
case neg
α : Type u_1
inst✝ : Preorder α
l : Ordnode α
x : α
o₁ : WithBot α
o₂ : WithTop α
hl : Valid' o₁ l ↑x
rs : ℕ
rl : Ordnode α
rx : α
rr : Ordnode α
hr : Valid' (↑x) (Ordnode.node rs rl rx rr) o₂
H1 : ¬l.size + (Ordnode.node rs rl rx rr).size ≤ 1
H2 : delta * l.size ≤ rl.size + rr.size
H3 : 2 * (rl.size + rr.size) ≤ 9 * l.size + 3 ∨ rl.size + rr.size ≤ 2
H3_0 : l.size = 0 → rl.size + rr.size ≤ 2
H3p : l.size > 0 → 2 * (rl.size + rr.size) ≤ 9 * l.size + 3
ablem : ∀ {a b : ℕ}, 1 ≤ a → a + b ≤ 2 → b ≤ 1
hlp : l.size > 0 → ¬rl.size + rr.size ≤ 1
h : ¬rl.size < ratio * rr.size
⊢ Valid' o₁ (l.node4L x rl rx rr) o₂

Tactic:
rcases Nat.eq_zero_or_pos (size rl) with rl0 | rl0

Result:
case neg.inl
α : Type u_1
inst✝ : Preorder α
l : Ordnode α
x : α
o₁ : WithBot α
o₂ : WithTop α
hl : Valid' o₁ l ↑x
rs : ℕ
rl : Ordnode α
rx : α
rr : Ordnode α
hr : Valid' (↑x) (Ordnode.node rs rl rx rr) o₂
H1 : ¬l.size + (Ordnode.node rs rl rx rr).size ≤ 1
H2 : delta * l.size ≤ rl.size + rr.size
H3 : 2 * (rl.size + rr.size) ≤ 9 * l.size + 3 ∨ rl.size + rr.size ≤ 2
H3_0 : l.size = 0 → rl.size + rr.size ≤ 2
H3p : l.size > 0 → 2 * (rl.size + rr.size) ≤ 9 * l.size + 3
ablem : ∀ {a b : ℕ}, 1 ≤ a → a + b ≤ 2 → b ≤ 1
hlp : l.size > 0 → ¬rl.size + rr.size ≤ 1
h : ¬rl.size < ratio * rr.size
rl0 : rl.size = 0
⊢ Valid' o₁ (l.node4L x rl rx rr) o₂

case neg.inr
α : Type u_1
inst✝ : Preorder α
l : Ordnode α
x : α
o₁ : WithBot α
o₂ : WithTop α
hl : Valid' o₁ l ↑x
rs : ℕ
rl : Ordnode α
rx : α
rr : Ordnode α
hr : Valid' (↑x) (Ordnode.node rs rl rx rr) o₂
H1 : ¬l.size + (Ordnode.node rs rl rx rr).size ≤ 1
H2 : delta * l.size ≤ rl.size + rr.size
H3 : 2 * (rl.size + rr.size) ≤ 9 * l.size + 3 ∨ rl.size + rr.size ≤ 2
H3_0 : l.size = 0 → rl.size + rr.size ≤ 2
H3p : l.size > 0 → 2 * (rl.size + rr.size) ≤ 9 * l.size + 3
ablem : ∀ {a b : ℕ}, 1 ≤ a → a + b ≤ 2 → b ≤ 1
hlp : l.size > 0 → ¬rl.size + rr.size ≤ 1
h : ¬rl.size < ratio * rr.size
rl0 : rl.size > 0
⊢ Valid' o₁ (l.node4L x rl rx rr) o₂

Proof state:
case pos.inl.inr
α : Type u_1
inst✝ : Preorder α
l : Ordnode α
x : α
o₁ : WithBot α
o₂ : WithTop α
hl : Valid' o₁ l ↑x
rs : ℕ
rl : Ordnode α
rx : α
rr : Ordnode α
hr : Valid' (↑x) (Ordnode.node rs rl rx rr) o₂
H1 : ¬l.size + (Ordnode.node rs rl rx rr).size ≤ 1
H2 : delta * l.size ≤ rl.size + rr.size
H3_0 : l.size = 0 → rl.size + rr.size ≤ 2
H3p : l.size > 0 → 2 * (rl.size + rr.size) ≤ 9 * l.size + 3
ablem : ∀ {a b : ℕ}, 1 ≤ a → a + b ≤ 2 → b ≤ 1
hlp : l.size > 0 → ¬rl.size + rr.size ≤ 1
h : rl.size < ratio * rr.size
rr0 : rr.size > 0
l0 : l.size = 0
H3 : rr.size + rl.size ≤ 2
this : BalancedSz rl.size rr.size
rl0 : rl.size > 0
rr1 : rr.size = 1
⊢ BalancedSz 0 1 ∧ BalancedSz (0 + 1 + 1) 1

Tactic:
decide

Result:
no goals

Proof state:
case neg.inl
α : Type u_1
inst✝ : Preorder α
l : Ordnode α
x : α
o₁ : WithBot α
o₂ : WithTop α
hl : Valid' o₁ l ↑x
rs : ℕ
rl : Ordnode α
rx : α
rr : Ordnode α
hr : Valid' (↑x) (Ordnode.node rs rl rx rr) o₂
H1 : ¬l.size + (Ordnode.node rs rl rx rr).size ≤ 1
H2 : delta = 0 ∨ l.size = 0
H3 : 2 * (rl.size + rr.size) ≤ 9 * l.size + 3 ∨ rl.size + rr.size ≤ 2
H3_0 : l.size = 0 → rl.size + rr.size ≤ 2
H3p : l.size > 0 → 2 * (rl.size + rr.size) ≤ 9 * l.size + 3
ablem : ∀ {a b : ℕ}, 1 ≤ a → a + b ≤ 2 → b ≤ 1
hlp : l.size > 0 → ¬rl.size + rr.size ≤ 1
rl0 : rl.size = 0
h : rr.size = 0
⊢ Valid' o₁ (l.node4L x rl rx rr) o₂

Tactic:
rw [hr.2.size_eq, rl0, h, H2.resolve_left (by decide)] at H1

Result:
case neg.inl
α : Type u_1
inst✝ : Preorder α
l : Ordnode α
x : α
o₁ : WithBot α
o₂ : WithTop α
hl : Valid' o₁ l ↑x
rs : ℕ
rl : Ordnode α
rx : α
rr : Ordnode α
hr : Valid' (↑x) (Ordnode.node rs rl rx rr) o₂
H1 : ¬0 + (0 + 0 + 1) ≤ 1
H2 : delta = 0 ∨ l.size = 0
H3 : 2 * (rl.size + rr.size) ≤ 9 * l.size + 3 ∨ rl.size + rr.size ≤ 2
H3_0 : l.size = 0 → rl.size + rr.size ≤ 2
H3p : l.size > 0 → 2 * (rl.size + rr.size) ≤ 9 * l.size + 3
ablem : ∀ {a b : ℕ}, 1 ≤ a → a + b ≤ 2 → b ≤ 1
hlp : l.size > 0 → ¬rl.size + rr.size ≤ 1
rl0 : rl.size = 0
h : rr.size = 0
⊢ Valid' o₁ (l.node4L x rl rx rr) o₂

Proof state:
case pos.inr.intro
α : Type u_1
inst✝ : Preorder α
l : Ordnode α
x : α
o₁ : WithBot α
o₂ : WithTop α
hl : Valid' o₁ l ↑x
rs : ℕ
rl : Ordnode α
rx : α
rr : Ordnode α
hr : Valid' (↑x) (Ordnode.node rs rl rx rr) o₂
H1 : ¬l.size + (Ordnode.node rs rl rx rr).size ≤ 1
H2 : delta * l.size ≤ rl.size + rr.size
H3_0 : l.size = 0 → rl.size + rr.size ≤ 2
H3p : l.size > 0 → 2 * (rl.size + rr.size) ≤ 9 * l.size + 3
ablem : ∀ {a b : ℕ}, 1 ≤ a → a + b ≤ 2 → b ≤ 1
hlp : l.size > 0 → ¬rl.size + rr.size ≤ 1
h : rl.size < ratio * rr.size
rr0 : rr.size > 0
l0 : l.size > 0
H3 : 2 * (rl.size + rr.size) ≤ 9 * l.size + 3
left✝ : rl.size ≤ delta * rr.size
hb₂ : rr.size ≤ delta * rl.size
⊢ BalancedSz l.size rl.size ∧ BalancedSz (l.size + rl.size + 1) rr.size

Tactic:
refine ⟨Or.inr ⟨?_, ?_⟩, Or.inr ⟨?_, ?_⟩⟩

Result:
case pos.inr.intro.refine_1
α : Type u_1
inst✝ : Preorder α
l : Ordnode α
x : α
o₁ : WithBot α
o₂ : WithTop α
hl : Valid' o₁ l ↑x
rs : ℕ
rl : Ordnode α
rx : α
rr : Ordnode α
hr : Valid' (↑x) (Ordnode.node rs rl rx rr) o₂
H1 : ¬l.size + (Ordnode.node rs rl rx rr).size ≤ 1
H2 : delta * l.size ≤ rl.size + rr.size
H3_0 : l.size = 0 → rl.size + rr.size ≤ 2
H3p : l.size > 0 → 2 * (rl.size + rr.size) ≤ 9 * l.size + 3
ablem : ∀ {a b : ℕ}, 1 ≤ a → a + b ≤ 2 → b ≤ 1
hlp : l.size > 0 → ¬rl.size + rr.size ≤ 1
h : rl.size < ratio * rr.size
rr0 : rr.size > 0
l0 : l.size > 0
H3 : 2 * (rl.size + rr.size) ≤ 9 * l.size + 3
left✝ : rl.size ≤ delta * rr.size
hb₂ : rr.size ≤ delta * rl.size
⊢ l.size ≤ delta * rl.size

case pos.inr.intro.refine_2
α : Type u_1
inst✝ : Preorder α
l : Ordnode α
x : α
o₁ : WithBot α
o₂ : WithTop α
hl : Valid' o₁ l ↑x
rs : ℕ
rl : Ordnode α
rx : α
rr : Ordnode α
hr : Valid' (↑x) (Ordnode.node rs rl rx rr) o₂
H1 : ¬l.size + (Ordnode.node rs rl rx rr).size ≤ 1
H2 : delta * l.size ≤ rl.size + rr.size
H3_0 : l.size = 0 → rl.size + rr.size ≤ 2
H3p : l.size > 0 → 2 * (rl.size + rr.size) ≤ 9 * l.size + 3
ablem : ∀ {a b : ℕ}, 1 ≤ a → a + b ≤ 2 → b ≤ 1
hlp : l.size > 0 → ¬rl.size + rr.size ≤ 1
h : rl.size < ratio * rr.size
rr0 : rr.size > 0
l0 : l.size > 0
H3 : 2 * (rl.size + rr.size) ≤ 9 * l.size + 3
left✝ : rl.size ≤ delta * rr.size
hb₂ : rr.size ≤ delta * rl.size
⊢ rl.size ≤ delta * l.size

case pos.inr.intro.refine_3
α : Type u_1
inst✝ : Preorder α
l : Ordnode α
x : α
o₁ : WithBot α
o₂ : WithTop α
hl : Valid' o₁ l ↑x
rs : ℕ
rl : Ordnode α
rx : α
rr : Ordnode α
hr : Valid' (↑x) (Ordnode.node rs rl rx rr) o₂
H1 : ¬l.size + (Ordnode.node rs rl rx rr).size ≤ 1
H2 : delta * l.size ≤ rl.size + rr.size
H3_0 : l.size = 0 → rl.size + rr.size ≤ 2
H3p : l.size > 0 → 2 * (rl.size + rr.size) ≤ 9 * l.size + 3
ablem : ∀ {a b : ℕ}, 1 ≤ a → a + b ≤ 2 → b ≤ 1
hlp : l.size > 0 → ¬rl.size + rr.size ≤ 1
h : rl.size < ratio * rr.size
rr0 : rr.size > 0
l0 : l.size > 0
H3 : 2 * (rl.size + rr.size) ≤ 9 * l.size + 3
left✝ : rl.size ≤ delta * rr.size
hb₂ : rr.size ≤ delta * rl.size
⊢ l.size + rl.size + 1 ≤ delta * rr.size

case pos.inr.intro.refine_4
α : Type u_1
inst✝ : Preorder α
l : Ordnode α
x : α
o₁ : WithBot α
o₂ : WithTop α
hl : Valid' o₁ l ↑x
rs : ℕ
rl : Ordnode α
rx : α
rr : Ordnode α
hr : Valid' (↑x) (Ordnode.node rs rl rx rr) o₂
H1 : ¬l.size + (Ordnode.node rs rl rx rr).size ≤ 1
H2 : delta * l.size ≤ rl.size + rr.size
H3_0 : l.size = 0 → rl.size + rr.size ≤ 2
H3p : l.size > 0 → 2 * (rl.size + rr.size) ≤ 9 * l.size + 3
ablem : ∀ {a b : ℕ}, 1 ≤ a → a + b ≤ 2 → b ≤ 1
hlp : l.size > 0 → ¬rl.size + rr.size ≤ 1
h : rl.size < ratio * rr.size
rr0 : rr.size > 0
l0 : l.size > 0
H3 : 2 * (rl.size + rr.size) ≤ 9 * l.size + 3
left✝ : rl.size ≤ delta * rr.size
hb₂ : rr.size ≤ delta * rl.size
⊢ rr.size ≤ delta * (l.size + rl.size + 1)