-- 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 node
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
⊢ Valid' o₁ (l.rotateL x (Ordnode.node rs rl rx rr)) o₂

Tactic:
have hlp : size l > 0 → ¬size rl + size rr ≤ 1 := fun l0 hb =>
  absurd (le_trans (le_trans (Nat.mul_le_mul_left _ l0) H2) hb) (by decide)

Result:
case node
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
⊢ Valid' o₁ (l.rotateL x (Ordnode.node rs rl rx rr)) o₂

Proof state:
case pos.inl.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_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 : rl.size + rr.size ≤ 2
this : BalancedSz 0 rr.size
rl0 : rl.size = 0
⊢ BalancedSz 0 0 ∧ BalancedSz (0 + 0 + 1) rr.size

Tactic:
rw [le_antisymm (balancedSz_zero.1 this.symm) rr0]

Result:
case pos.inl.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_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 : rl.size + rr.size ≤ 2
this : BalancedSz 0 rr.size
rl0 : rl.size = 0
⊢ BalancedSz 0 0 ∧ BalancedSz (0 + 0 + 1) 1

Proof state:
case pos.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
rr0 : rr.size > 0
l0 : l.size > 0
⊢ BalancedSz l.size rl.size ∧ BalancedSz (l.size + rl.size + 1) rr.size

Tactic:
replace H3 := H3p l0

Result:
case pos.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 : 2 * (rl.size + rr.size) ≤ 9 * l.size + 3
⊢ BalancedSz l.size rl.size ∧ BalancedSz (l.size + rl.size + 1) rr.size

Proof state:
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
⊢ 0 + (0 + 0 + 1) ≤ 1

Tactic:
decide

Result:
no goals

Proof state:
case nil
α : Type u_1
inst✝ : Preorder α
l : Ordnode α
x : α
o₁ : WithBot α
o₂ : WithTop α
hl : Valid' o₁ l ↑x
hr : Valid' (↑x) nil o₂
H1 : ¬l.size + nil.size ≤ 1
H2 : delta * l.size < nil.size
H3 : 2 * nil.size ≤ 9 * l.size + 5 ∨ nil.size ≤ 3
⊢ Valid' o₁ (l.rotateL x nil) o₂

Tactic:
cases H2

Result:
no goals

Proof state:
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 * 0 + 3 ∨ rl.size + rr.size ≤ 2
l0 : l.size = 0
h : 2 * (rl.size + rr.size) ≤ 9 * 0 + 3
⊢ 9 * 0 + 3 ≤ 2 * 2

Tactic:
decide

Result:
no goals

Proof state:
case pos.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
rr0 : rr.size > 0
l0 : l.size = 0
⊢ BalancedSz l.size rl.size ∧ BalancedSz (l.size + rl.size + 1) rr.size

Tactic:
rw [l0]

Result:
case pos.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
rr0 : rr.size > 0
l0 : l.size = 0
⊢ BalancedSz 0 rl.size ∧ BalancedSz (0 + rl.size + 1) rr.size