roseking's picture
Add lean source and binary files (part 46)
5d5048e verified
Raw History Blame Contribute Delete
4.38 kB
import OAI.Combinatorics.LowSpaceSubsetSum.Storage.IntervalDomainExecution
namespace OAI
/-! # The sorted outside domain from the remaining canonical interval -/
noncomputable section
namespace LowSpaceSubsetSum.CanonicalBackground
variable {n : ℕ}
private theorem in_three_intervals (m x : ℕ) :
(∃ j : Fin 3, j.val * m ≤ x ∧ x < j.val * m + m) ↔ x < 3 * m := by
constructor
· rintro ⟨j, hj⟩
fin_cases j <;> (have h := hj.2; norm_num at h; nlinarith only [h])
· intro h
by_cases h0 : x < m
· exact ⟨0, by simp; omega⟩
· by_cases h1 : x < 2 * m
· exact ⟨1, by simp; omega⟩
· exact ⟨2, by simp; omega⟩
theorem raw_mem (I : Instance n) (e : Equiv.Perm (Fin n)) (signs : Finset (Fin n))
(j : Fin 3) (x : Fin n) :
x ∈ (canonicalRepresentationData I).zeroSetup.rawMixers (e, signs) j ↔
j.val * mixerSize n ≤ (e.symm x).val ∧
(e.symm x).val < j.val * mixerSize n + mixerSize n := by
change x ∈ permuteSubset e (indexInterval n (j.val * mixerSize n) (mixerSize n)) ↔ _
simp only [permuteSubset, Finset.mem_map, indexInterval, Finset.mem_filter,
Finset.mem_univ, true_and, Equiv.toEmbedding_apply]
constructor
· rintro ⟨a, ha, rfl⟩
simpa only [Equiv.symm_apply_apply] using ha
· intro hx
exact ⟨e.symm x, hx, e.apply_symm_apply x⟩
theorem union_mem (I : Instance n) (e : Equiv.Perm (Fin n)) (signs : Finset (Fin n))
(x : Fin n) :
x ∈ (canonicalRepresentationData I).zeroSetup.mixerUnion (e, signs) ↔
(e.symm x).val < 3 * mixerSize n := by
let R := (canonicalRepresentationData I).zeroSetup
have hordered : x ∈ R.mixerUnion (e, signs) ↔
∃ j : Fin 3, x ∈ R.orderedMixers (e, signs) j := by
simp [RepresentationSetup.mixerUnion, Fin.exists_fin_succ]
have hraw : (∃ j : Fin 3, x ∈ R.orderedMixers (e, signs) j) ↔
∃ j : Fin 3, x ∈ R.rawMixers (e, signs) j := by
constructor
· rintro ⟨j, hj⟩
exact ⟨R.mixerOrder (e, signs) j, hj⟩
· rintro ⟨j, hj⟩
refine ⟨(R.mixerOrder (e, signs)).symm j, ?_⟩
simpa only [RepresentationSetup.orderedMixers, Equiv.apply_symm_apply] using hj
rw [hordered, hraw]
change (∃ j : Fin 3, x ∈ (canonicalRepresentationData I).zeroSetup.rawMixers (e, signs) j) ↔ _
simp_rw [raw_mem]
exact in_three_intervals _ _
def run (v : Vector (Fin n) n) : List (Fin n) × ℕ :=
IntervalDomainExecution.run v (3 * mixerSize n) (n - 3 * mixerSize n)
theorem domain_eq (I : Instance n) (e : Equiv.Perm (Fin n)) (signs : Finset (Fin n)) :
permuteSubset e (indexInterval n (3 * mixerSize n) (n - 3 * mixerSize n)) =
Finset.univ \ (canonicalRepresentationData I).zeroSetup.mixerUnion (e, signs) := by
have hm : 3 * mixerSize n ≤ n := by unfold mixerSize; omega
ext x
simp only [Finset.mem_sdiff, Finset.mem_univ, true_and, union_mem]
simp only [permuteSubset, Finset.mem_map, indexInterval, Finset.mem_filter,
Finset.mem_univ, true_and, Equiv.toEmbedding_apply]
constructor
· rintro ⟨a, ha, rfl⟩
simpa only [Equiv.symm_apply_apply] using (show ¬ a.val < 3 * mixerSize n by omega)
· intro hx
refine ⟨e.symm x, ?_, e.apply_symm_apply x⟩
have hb := (e.symm x).isLt
omega
theorem value (I : Instance n) (v : Vector (Fin n) n) (e : Equiv.Perm (Fin n))
(hv : ∀ i : Fin n, v[i.val] = e i) (signs : Finset (Fin n)) :
(run v).1 =
(Finset.univ \ (canonicalRepresentationData I).zeroSetup.mixerUnion (e, signs)).sort (· ≤ ·) := by
rw [run, IntervalDomainExecution.source, CompressionDomains.domain_value v e hv,
domain_eq I e signs]
theorem work (v : Vector (Fin n) n) : (run v).2 ≤ 40 * (n + 1) ^ 2 :=
IntervalDomainExecution.work v _ _
theorem length_le (v : Vector (Fin n) n) : (run v).1.length ≤ n := by
rw [run, IntervalDomainExecution.source]
change ((MeasuredSort.sort (fun x y : Fin n => (decide (x ≤ y), 1))
(CompressionDomains.unsorted v (indexInterval n (3 * mixerSize n)
(n - 3 * mixerSize n)))).1).length ≤ n
rw [MeasuredSort.sort_value, List.Perm.length_eq (List.mergeSort_perm _ _)]
simpa only [CompressionDomains.unsorted, List.length_map] using
CompressionDomains.positions_length (indexInterval n (3 * mixerSize n) (n - 3 * mixerSize n))
end LowSpaceSubsetSum.CanonicalBackground
end
end OAI