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Add lean source and binary files (part 64)
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import Mathlib
import OAI.Computability.VertexCover.Analysis.GraphComplete
import OAI.Computability.VertexCover.Reduction.ReductionSound
import OAI.Computability.VertexCover.Reduction.DenseEncodingBound
namespace OAI
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namespace VertexCover.ClauseProjection
open UniqueGames
noncomputable section
def falseFormula : BinaryFormula.Formula :=
⟨[#v[⟨0,true⟩, ⟨0,true⟩, ⟨0,true⟩], #v[⟨0,false⟩, ⟨0,false⟩, ⟨0,false⟩]]⟩
theorem falseFormula_unsat : ¬falseFormula.Satisfiable := by
rintro ⟨A, hA⟩
have hpos := hA #v[⟨0,true⟩, ⟨0,true⟩, ⟨0,true⟩] (by simp [falseFormula])
have hneg := hA #v[⟨0,false⟩, ⟨0,false⟩, ⟨0,false⟩] (by simp [falseFormula])
cases h : A 0 <;> simp [BinaryFormula.Clause.eval, BinaryFormula.Literal.eval, h] at hpos hneg
def inputFormula (input : List Bool) : BinaryFormula.Formula :=
(BinaryEncoding.decodeFormula input).getD falseFormula
def InputSAT (input : List Bool) : Prop :=
∃ F, BinaryEncoding.decodeFormula input = some F ∧ F.Satisfiable
theorem inputFormula_sat (input : List Bool) : (inputFormula input).Satisfiable ↔ InputSAT input := by
unfold inputFormula InputSAT
cases h : BinaryEncoding.decodeFormula input with
| none => simp [falseFormula_unsat]
| some F => simp
def binaryReduction (σ : ℝ) (hσ : 0 < σ) (input : List Bool) : VertexCover.LabelCover :=
reduction σ hσ (BinaryFormula.dense (inputFormula input))
theorem binaryReduction_complete (σ : ℝ) (hσ : 0 < σ) (input : List Bool)
(h : InputSAT input) :
∃ A : (binaryReduction σ hσ input).Labeling,
∀ e, (binaryReduction σ hσ input).Satisfies A e :=
reduction_complete σ hσ _ (BinaryFormula.dense_completeness _ ((inputFormula_sat input).mpr h))
theorem binaryReduction_sound (σ : ℝ) (hσ : 0 < σ) (input : List Bool)
(h : ¬InputSAT input) : (binaryReduction σ hσ input).value < σ := by
apply reduction_sound
intro hs
exact h ((inputFormula_sat input).mp (BinaryFormula.dense_reflects _ hs))
end
end VertexCover.ClauseProjection
namespace VertexCover
noncomputable section
def rawGraph (m : ℕ) (hm : 4 ≤ m) (input : List Bool) : ExplicitGraph :=
(ClauseProjection.binaryReduction (Parameters.σ m)
(Parameters.σ_between m hm).1 input).explicitGraph m
theorem rawGraph_completeness (m : ℕ) (hm : 4 ≤ m) (input : List Bool)
(h : ThreeSAT input) :
((rawGraph m hm input).coverNumber : ℝ) <
((1:ℝ)/2+1/(m:ℝ)) * (rawGraph m hm input).n := by
have hc := ClauseProjection.binaryReduction_complete (Parameters.σ m)
(Parameters.σ_between m hm).1 input h
obtain ⟨A, hA⟩ := hc
exact LabelCover.explicitGraph_complete _ m hm A hA
theorem rawLabelCover_soundness (m : ℕ) (hm : 4 ≤ m) (input : List Bool)
(h : ¬ ThreeSAT input) :
(ClauseProjection.binaryReduction (Parameters.σ m)
(Parameters.σ_between m hm).1 input).value < Parameters.σ m :=
ClauseProjection.binaryReduction_sound _ _ input h
end
end VertexCover
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end OAI