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Add lean source and binary files (part 47)
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import Mathlib
import OAI.Combinatorics.MatchingCount.Probability.AdaptiveLaw
import OAI.Combinatorics.MatchingCount.Sampling.RankOrder
namespace OAI
namespace MatchingFPRAS.UnitRefresh.Materialized
open Finset
variable {V : Type} [Fintype V] {m : ℕ}
def RowBound (t : Table) (w : Fin m → ℕ) : Prop := ∀ a r,read t a.val r ≤ w a
def mergeEnvelope (w : Fin m → ℕ) (l p : Fin m) (s : ℕ) : Fin m → ℕ :=
fun a=>if a=l then 1 else if a=p then 2^s*w l*w p else w a
lemma mergeEnvelope_pos (w : Fin m → ℕ) (hw : ∀ a,1≤w a) (l p : Fin m) (s : ℕ) :
∀ a,1 ≤ mergeEnvelope w l p s a := by
intro a
unfold mergeEnvelope
split_ifs
· exact le_rfl
· have hl := hw l
have hp := hw p
exact Nat.one_le_iff_ne_zero.mpr (by positivity)
· exact hw a
lemma mergeEnvelope_prod (w : Fin m → ℕ) (l p : Fin m) (h : p≠l) (s : ℕ) :
(∏ a,mergeEnvelope w l p s a)=2^s*∏ a,w a := by
have hp : p∈(univ : Finset (Fin m)).erase l := by simp [h]
rw [←mul_prod_erase univ (mergeEnvelope w l p s) (mem_univ l),
←mul_prod_erase (univ.erase l) (mergeEnvelope w l p s) hp,
←mul_prod_erase univ w (mem_univ l),←mul_prod_erase (univ.erase l) w hp]
have he : (∏ a∈(univ.erase l).erase p,mergeEnvelope w l p s a)=
∏ a∈(univ.erase l).erase p,w a := by
apply prod_congr rfl
intro a ha
have hal : a≠l := (mem_erase.mp (mem_erase.mp ha).2).1
have hap : a≠p := (mem_erase.mp ha).1
simp [mergeEnvelope,hal,hap]
rw [he]
simp only [mergeEnvelope,↓reduceIte,h]
ring
omit [Fintype V] in
lemma entry_rowBound (bags : V → Finset (Fin m)) (R : Finset V)
(parent : Fin m → Option (Fin m)) (l : Fin m) (t : Table) (w : Fin m → ℕ)
(_ : ∀ a,1≤w a) (ht : RowBound t w) :
∀ a r,entry bags R parent l a t r ≤
match parent l with
| none => w a
| some p => mergeEnvelope w l p (sharedCount bags R l) a := by
intro a r
unfold entry
cases hp : parent l with
| none =>
simp only
split_ifs with h
· subst a; exact ht l _
· exact ht a r
| some p =>
simp only
unfold mergeEnvelope
split_ifs with h h'
· exact le_rfl
· subst a
calc
_ ≤ ∑ k∈range (sharedCount bags R l+1),
(sharedCount bags R l).choose k*w l*w p := by
apply sum_le_sum
intro k hk
exact Nat.mul_le_mul (Nat.mul_le_mul_left _ (ht l _)) (ht p _)
_ = 2^(sharedCount bags R l)*w l*w p := by
rw [←sum_mul,←sum_mul,Nat.sum_range_choose]
· exact ht a r
omit [Fintype V] in
lemma update_rowBound (bags : V → Finset (Fin m)) (R : Finset V)
(parent : Fin m → Option (Fin m)) (l : Fin m) (B : ℕ) (t : Table) (w : Fin m → ℕ)
(hw : ∀ a,1≤w a) (ht : RowBound t w) :
RowBound (update bags R parent l B t)
(match parent l with | none=>w | some p=>mergeEnvelope w l p (sharedCount bags R l)) := by
intro a r
rw [update,read_tabulate]
split_ifs
· have h := entry_rowBound bags R parent l t w hw ht a r
cases hh : parent l <;> simpa only [hh] using h
· exact Nat.zero_le _
lemma sharedCount_le_card (bags : V → Finset (Fin m)) (R : Finset V) (l : Fin m) :
sharedCount bags R l≤Fintype.card V := by
exact (card_le_card (filter_subset _ _)).trans (card_le_univ _)
lemma run_envelope (bags : V → Finset (Fin m)) (parent : Fin m → Option (Fin m))
(hp : ∀ l p,parent l=some p → p≠l) (ls : List (Fin m)) (R : Finset V)
(t : Table) (w : Fin m → ℕ) (hw : ∀ a,1≤w a) (ht : RowBound t w) :
∃ v : Fin m → ℕ,(∀ a,1≤v a) ∧ RowBound (run bags parent ls R t) v ∧
(∏ a,v a) ≤ 2^(Fintype.card V*ls.length)*(∏ a,w a) := by
induction ls generalizing R t w with
| nil => exact ⟨w,hw,ht,by simp⟩
| cons l ls ih =>
let v := match parent l with | none=>w | some p=>mergeEnvelope w l p (sharedCount bags R l)
have hv : ∀ a,1≤v a := by
cases hh : parent l with
| none => simpa [v,hh] using hw
| some p => simpa only [v,hh] using mergeEnvelope_pos w hw l p (sharedCount bags R l)
have hvt : RowBound (update bags R parent l (Fintype.card V*ls.length) t) v :=
update_rowBound bags R parent l _ t w hw ht
have hprod : (∏ a,v a) ≤ 2^(Fintype.card V)*(∏ a,w a) := by
cases hh : parent l with
| none =>
simp only [v,hh]
exact Nat.le_mul_of_pos_left _ (by positivity)
| some p =>
simp only [v,hh]
rw [mergeEnvelope_prod w l p (hp l p hh)]
exact Nat.mul_le_mul_right _ (Nat.pow_le_pow_right (by decide) (sharedCount_le_card bags R l))
obtain ⟨z,hz,hzt,hzp⟩ := ih (trim bags R l) _ v hv hvt
refine ⟨z,hz,hzt,?_⟩
apply hzp.trans
calc
_ ≤ 2^(Fintype.card V*ls.length)*(2^Fintype.card V*∏ a,w a) := Nat.mul_le_mul_left _ hprod
_ = _ := by rw [List.length_cons,Nat.mul_add,Nat.mul_one,pow_add]; ring
lemma run_entry_le (bags : V → Finset (Fin m)) (parent : Fin m → Option (Fin m))
(hp : ∀ l p,parent l=some p → p≠l) (ls : List (Fin m)) (R : Finset V)
(t : Table) (w : Fin m → ℕ) (hw : ∀ a,1≤w a) (ht : RowBound t w) (a : Fin m) (r : ℕ) :
read (run bags parent ls R t) a.val r ≤ 2^(Fintype.card V*ls.length)*(∏ a,w a) := by
obtain ⟨v,hv,hvt,hvp⟩:=run_envelope bags parent hp ls R t w hw ht
exact (hvt a r).trans ((single_le_prod (fun x _=>hv x) (mem_univ a)).trans hvp)
lemma pairingCount_pow_bound (n : ℕ) : pairingCount n ≤ 2^(n*n) := by
calc
_ ≤ n^(n/2) := pairingCount_le_half_power n
_ ≤ (2^n)^(n/2) := Nat.pow_le_pow_left (Nat.le_of_lt n.lt_two_pow_self) _
_ = 2^(n*(n/2)) := (pow_mul _ _ _).symm
_ ≤ 2^(n*n) := Nat.pow_le_pow_right (by decide) (Nat.mul_le_mul_left _ (Nat.div_le_self _ _))
lemma initial_rowBound (B : ℕ) : RowBound (initial m B) (fun _ : Fin m=>2^(B*B)) := by
intro a r
rw [initial,read_tabulate]
split_ifs with h
· exact (pairingCount_pow_bound r).trans
(Nat.pow_le_pow_right (by decide) (Nat.mul_le_mul h h))
· exact Nat.zero_le _
lemma run_initial_size (bags : V → Finset (Fin m)) (parent : Fin m → Option (Fin m))
(hp : ∀ l p,parent l=some p → p≠l) (ls : List (Fin m)) (R : Finset V)
(B : ℕ) (a : Fin m) (r : ℕ) :
(read (run bags parent ls R (initial m B)) a.val r).size ≤
Fintype.card V*ls.length+B*B*m+1 := by
have h := run_entry_le bags parent hp ls R (initial m B) (fun _=>2^(B*B))
(fun _=>Nat.one_le_iff_ne_zero.mpr (by positivity)) (initial_rowBound B) a r
simp only [prod_const,card_univ,Fintype.card_fin,←pow_mul,←pow_add] at h
simpa only [Nat.size_pow] using Nat.size_le_size h
lemma run_initial_product_le (bags : V → Finset (Fin m)) (parent : Fin m → Option (Fin m))
(hp : ∀ l p,parent l=some p → p≠l) (ls : List (Fin m)) (R : Finset V) (B : ℕ) :
(∏ a : Fin m,read (run bags parent ls R (initial m B)) a.val 0) ≤
2^(Fintype.card V*ls.length+B*B*m) := by
obtain ⟨v,hv,hvt,hvp⟩ := run_envelope bags parent hp ls R (initial m B)
(fun _=>2^(B*B)) (fun _=>Nat.one_le_iff_ne_zero.mpr (by positivity)) (initial_rowBound B)
apply (prod_le_prod (fun a _=>hvt a 0)).trans
simpa only [prod_const,card_univ,Fintype.card_fin,←pow_mul,←pow_add] using hvp
end MatchingFPRAS.UnitRefresh.Materialized
end OAI