import OAI.GameTheory.SnakyTwentyOne.Cards.Height21Part01 import OAI.GameTheory.SnakyTwentyOne.Certificate.Summary import OAI.GameTheory.SnakyTwentyOne.Model import OAI.GameTheory.SnakyTwentyOne.Semantics.Game import OAI.GameTheory.SnakyTwentyOne.Semantics.Geometry import OAI.GameTheory.SnakyTwentyOne.Semantics.Policy import OAI.GameTheory.SnakyTwentyOne.Semantics.Replies namespace OAI namespace SnakyPrototype theorem empty_board_wins_21 : WinsIn HasSnaky 21 ∅ ∅ := by exact Certificate21.row_works_727 ∅ ∅ (by simp) (by simp [Certificate21.required_727]) (by simp) end SnakyPrototype namespace SnakyPrototype open OrdinaryStrategy theorem snaky_winning_strategy_21_with_legal_states : ∃ σ : Policy Cell, (∀ r M B, σ r M B ∉ M ∧ σ r M B ∉ B) ∧ ∀ β : ℕ → Cell, LegalRepliesBeforeFinal σ 21 β ∅ ∅ → HasSnaky (playState σ 21 β ∅ ∅ 21).1 ∧ (playState σ 21 β ∅ ∅ 21).1.card = 21 ∧ Disjoint (playState σ 21 β ∅ ∅ 21).1 (playState σ 21 β ∅ ∅ 20).2 ∧ ∀ k, k < 21 → Disjoint (playState σ 21 β ∅ ∅ k).1 (playState σ 21 β ∅ ∅ k).2 ∧ (playState σ 21 β ∅ ∅ k).2.card = k := by refine ⟨policy HasSnaky, policy_fresh HasSnaky, ?_⟩ intro β hβ refine ⟨policy_wins (fun M N hMN hw => HasSnaky.mono hw hMN) 21 β ∅ ∅ empty_board_wins_21 hβ, ?_, ?_, ?_⟩ · simpa using playState_maker_card (policy HasSnaky) (policy_fresh HasSnaky) 21 β ∅ ∅ 21 · exact final_maker_disjoint (policy HasSnaky) (policy_fresh HasSnaky) 20 β ∅ ∅ (by simp) hβ · intro k hk simpa using playState_legal_prefix (policy HasSnaky) (policy_fresh HasSnaky) 21 β ∅ ∅ (by simp) hβ k hk theorem snaky_winning_strategy_21 : ∃ σ : Policy Cell, (∀ r M B, σ r M B ∉ M ∧ σ r M B ∉ B) ∧ ∀ β : ℕ → Cell, LegalRepliesBeforeFinal σ 21 β ∅ ∅ → HasSnaky (playState σ 21 β ∅ ∅ 21).1 := by obtain ⟨σ, hσ, hw⟩ := snaky_winning_strategy_21_with_legal_states exact ⟨σ, hσ, fun β hβ => (hw β hβ).1⟩ end SnakyPrototype end OAI