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Add lean source and binary files (part 62)
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import OAI.Computability.PerfectCompleteness.Machines.BinaryFormulaLemmas
namespace OAI
section
namespace PerfectCompleteness.BinaryOccurrenceRename
open BinaryFormula UniqueGamesTheorem.Foundations
theorem literal_mem_names (F : Formula) (c : Clause) (hc : c ∈ F.clauses)
(i : Fin 3) : (c)[i].name ∈ sourceNames F := by
apply List.mem_flatMap.mpr
refine ⟨c, hc, ?_⟩
have hi : i = 0 ∨ i = 1 ∨ i = 2 := by omega
rcases hi with rfl | rfl | rfl <;> simp [clauseNames]
def nameIndex (F : Formula) (name : Nat) (mem : name ∈ sourceNames F) :
Fin (sourceNames F).length :=
⟨(sourceNames F).idxOf name, List.idxOf_lt_length_of_mem mem⟩
def literal (F : Formula) (l : Literal) (mem : l.name ∈ sourceNames F) :
Target.Literal (sourceNames F).length :=
⟨nameIndex F l.name mem, l.positive⟩
def clause (F : Formula) (c : Clause) (mem : c ∈ F.clauses) :
Target.Clause (sourceNames F).length :=
#v[literal F (c)[0] (literal_mem_names F c mem 0),
literal F (c)[1] (literal_mem_names F c mem 1),
literal F (c)[2] (literal_mem_names F c mem 2)]
def renamed (F : Formula) : Target.Formula where
«variables» := (sourceNames F).length
clauses := F.clauses.attach.map (fun c => clause F c.val c.property)
def restrictAssignment (F : Formula) (A : Nat → Bool) :
Fin (sourceNames F).length → Bool :=
fun i => A (sourceNames F)[i.val]
def extendAssignment (F : Formula) (A : Fin (sourceNames F).length → Bool) : Nat → Bool :=
fun name => if mem : name ∈ sourceNames F then A (nameIndex F name mem) else false
@[simp] theorem nameIndex_reads_name (F : Formula) (name : Nat)
(mem : name ∈ sourceNames F) : (sourceNames F)[(nameIndex F name mem).val] = name :=
List.getElem_idxOf _
@[simp] theorem clause_eval_restrict (F : Formula) (c : Clause) (mem : c ∈ F.clauses)
(A : Nat → Bool) : (clause F c mem).eval (restrictAssignment F A) = c.eval A := by
simp [clause, literal, Target.Clause.eval, Target.Literal.eval,
BinaryFormula.Clause.eval, BinaryFormula.Literal.eval, restrictAssignment]
@[simp] theorem clause_eval_extend (F : Formula) (c : Clause) (mem : c ∈ F.clauses)
(A : Fin (sourceNames F).length → Bool) :
(clause F c mem).eval A = c.eval (extendAssignment F A) := by
have evalLiteral (l : Literal) (hl : l.name ∈ sourceNames F) :
(literal F l hl).eval A = l.eval (extendAssignment F A) := by
simp only [literal, Target.Literal.eval, BinaryFormula.Literal.eval,
extendAssignment, dite_eq_left hl]
rfl
simp [clause, Target.Clause.eval, BinaryFormula.Clause.eval, evalLiteral]
@[simp] theorem renamed_clause_count (F : Formula) :
(renamed F).clauses.length = F.clauses.length := by simp [renamed]
@[simp] theorem renamed_variable_count (F : Formula) :
(renamed F).variables = 3 * F.clauses.length := by
exact clauseNames_flat_length F.clauses
theorem renamed_satisfiable_iff (F : Formula) : (renamed F).Satisfiable ↔ F.Satisfiable := by
constructor
· rintro ⟨A, hA⟩
refine ⟨extendAssignment F A, ?_⟩
intro c mem
have hc : clause F c mem ∈ (renamed F).clauses :=
List.mem_map.mpr ⟨⟨c, mem⟩, by simp, rfl⟩
exact (clause_eval_extend F c mem A).symm.trans (hA _ hc)
· rintro ⟨A, hA⟩
refine ⟨restrictAssignment F A, ?_⟩
intro c mem
obtain ⟨original, _, rfl⟩ := List.mem_map.mp mem
exact (clause_eval_restrict F original.val original.property A).trans
(hA original.val original.property)
theorem nat_bits_injective : Function.Injective Nat.bits := by
intro a b same
have decoded := congrArg BinaryEncoding.bitsValue same
simpa only [BinaryEncoding.bitsValue_bits] using decoded
theorem idxOf_binary_payloads (names : List Nat) (name : Nat) :
(names.map Nat.bits).idxOf name.bits = names.idxOf name := by
induction names with
| nil => rfl
| cons first names ih =>
by_cases same : first = name
· subst first
simp
· have different : first.bits ≠ name.bits := fun h => same (nat_bits_injective h)
simp only [List.map_cons, List.idxOf_cons, beq_false_of_ne same,
beq_false_of_ne different, ih]
theorem renamed_encoding_bound (F : Formula) :
(Complexity.formulaBits (renamed F)).length ≤
9 * F.clauses.length * F.clauses.length + 10 * F.clauses.length + 2 := by
have h := Complexity.formulaBits_length_le (renamed F)
simp only [renamed_clause_count, renamed_variable_count] at h
nlinarith
theorem renamed_encoding_bound_bits (F : Formula) :
(Complexity.formulaBits (renamed F)).length ≤
9 * (BinaryEncoding.formulaBits F).length * (BinaryEncoding.formulaBits F).length +
10 * (BinaryEncoding.formulaBits F).length + 2 := by
have h := renamed_encoding_bound F
have hm : F.clauses.length ≤ (BinaryEncoding.formulaBits F).length :=
(BinaryEncoding.clauses_length_lt_bits F.clauses).le
have hsq := Nat.mul_self_le_mul_self hm
nlinarith
end PerfectCompleteness.BinaryOccurrenceRename
end
end OAI