From 59709e23755cc1c76bf7b3fb0dd753ed5e0d3b7a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maximilian=20Ke=C3=9Fler?= <git@maximilian-kessler.de>
Date: Sat, 11 Nov 2023 11:44:06 +0100
Subject: [PATCH] rework -r option: solve state in reverse order

---
 include/game_state.h   |  2 ++
 include/game_state.hpp |  7 +++++++
 src/main.cpp           | 24 +++++++++++++++---------
 3 files changed, 24 insertions(+), 9 deletions(-)

diff --git a/include/game_state.h b/include/game_state.h
index 4b4aa95..b9ee2a5 100644
--- a/include/game_state.h
+++ b/include/game_state.h
@@ -218,6 +218,7 @@ public:
     virtual void play(hand_index_t index) = 0;
 
     virtual void rotate_next_draw(const Card& card) = 0;
+    virtual ActionType last_action_type() const = 0;
     virtual void revert() = 0;
 
     virtual void modify_clues(clue_t change) = 0;
@@ -283,6 +284,7 @@ public:
     void play(hand_index_t index) final;
 
     void rotate_next_draw(const Card& card) final;
+    ActionType last_action_type() const final;
 
     void revert() final;
 
diff --git a/include/game_state.hpp b/include/game_state.hpp
index e063bcc..9dbded4 100644
--- a/include/game_state.hpp
+++ b/include/game_state.hpp
@@ -678,6 +678,13 @@ namespace Hanabi {
         std::swap(*card_it, _draw_pile.front());
     }
 
+    template<suit_t num_suits, player_t num_players, hand_index_t hand_size>
+    ActionType HanabiState<num_suits, num_players, hand_size>::last_action_type() const
+    {
+      assert(not _actions_log.empty());
+      return _actions_log.top().action_type;
+    }
+
     template<suit_t num_suits, player_t num_players, hand_index_t hand_size>
     probability_t HanabiState<num_suits, num_players, hand_size>::evaluate_state() {
         ASSERT(_relative_representation.initialized);
diff --git a/src/main.cpp b/src/main.cpp
index b4374ad..5694ee7 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -36,13 +36,17 @@ namespace Hanabi {
         }
         game.state->init_backtracking_information();
         auto start = std::chrono::high_resolution_clock::now();
-        auto res = game.state->evaluate_state();
+        boost::rational<probability_base_type> result;
+        if (not print_remaining_states) {
+          result = game.state->evaluate_state();
+        }
         auto end = std::chrono::high_resolution_clock::now();
 
         std::cout.precision(10);
-        if (not (quiet and print_remaining_states)) {
+
+        if (not print_remaining_states) {
           std::cout << "Probability with optimal play: ";
-          print_probability(std::cout, res) << std::endl;
+          print_probability(std::cout, result) << std::endl;
         }
         if (not quiet) {
           std::cout << "Took " << std::chrono::duration_cast<std::chrono::milliseconds>(end - start) << "." << std::endl;
@@ -52,22 +56,24 @@ namespace Hanabi {
 
         if (print_remaining_states)
         {
-          for(size_t remaining_cards = game.state->draw_pile_size(); remaining_cards > 0; remaining_cards--) {
-            game.forward_until(100, remaining_cards);
+          size_t const max_draw_pile_size = game.state->draw_pile_size();
+          game.forward_until(100, 1);
+          for(size_t remaining_cards = 1; remaining_cards <= max_draw_pile_size; remaining_cards++) {
+            game.revert_until(remaining_cards);
             if (all_clues) {
               clue_t original_num_clues = game.state->num_clues();
               for(clue_t num_clues = 0; num_clues <= 8; num_clues++) {
                 game.state->set_clues(num_clues);
-                res = game.state->evaluate_state();
+                result = game.state->evaluate_state();
                 std::cout << "Probability with " << remaining_cards << " cards left in deck and " << +num_clues
                       << " clues (" << std::showpos << +(num_clues - original_num_clues) << "): " << std::noshowpos;
-                print_probability(std::cout, res) << std::endl;
+                print_probability(std::cout, result) << std::endl;
               }
               game.state->set_clues(original_num_clues);
             } else {
-              res = game.state->evaluate_state();
+              result = game.state->evaluate_state();
               std::cout << "Probability with " << remaining_cards << " cards left in deck: ";
-              print_probability(std::cout, res) << std::endl;
+              print_probability(std::cout, result) << std::endl;
             }
           }
         }