game_state: support clue starved variants

include/game_state.h

@@ -72,7 +72,7 @@ namespace Hanabi
   public:
     HanabiState() = default;
 
-    explicit HanabiState(const std::vector<Card> & deck, uint8_t score_goal = 5 * num_suits);
+    explicit HanabiState(const std::vector<Card> & deck, uint8_t score_goal = 5 * num_suits, clue_t num_clues_gained_on_discard_or_stack_finished = 1);
 
     void give_clue() final;
 
@@ -219,6 +219,9 @@ namespace Hanabi
     static constexpr uint8_t no_endgame = std::numeric_limits<uint8_t>::max();
 
     // Usual game state
+    clue_t const _clues_gained_on_discard_or_stack_finished { 1 };
+    uint8_t const _score_goal{};
+
     player_t _turn{};
     clue_t _num_clues{};
     std::uint8_t _weighted_draw_pile_size{};
@@ -230,7 +233,6 @@ namespace Hanabi
     // further values of game state that are technically determined, but we update them anyway
     int8_t _pace{};
     uint8_t _score{};
-    uint8_t _score_goal{};
 
     // For reverting the current game
     std::stack<BacktrackAction> _actions_log;

include/game_state.hpp

@@ -65,10 +65,11 @@ namespace Hanabi
   }
 
   template<suit_t num_suits, player_t num_players, hand_index_t hand_size>
-  HanabiState<num_suits, num_players, hand_size>::HanabiState(const std::vector<Card> & deck, uint8_t score_goal):
-        _turn(0), _num_clues(max_num_clues), _weighted_draw_pile_size(deck.size()), _stacks(), _hands(), _draw_pile()
+  HanabiState<num_suits, num_players, hand_size>::HanabiState(const std::vector<Card> & deck, uint8_t score_goal, clue_t num_clues_gained_on_discard_or_stack_finished):
+        _clues_gained_on_discard_or_stack_finished(num_clues_gained_on_discard_or_stack_finished)
+        , _score_goal(score_goal), _turn(0), _num_clues(max_num_clues), _weighted_draw_pile_size(deck.size()), _stacks(), _hands(), _draw_pile()
         , _endgame_turns_left(no_endgame), _pace(deck.size() - score_goal - num_players * (hand_size - 1)), _score(0)
-        , _score_goal(score_goal), _actions_log(), _relative_representation(), _position_tablebase()
+        , _actions_log(), _relative_representation(), _position_tablebase()
         , _enumerated_states(0)
   {
     std::ranges::fill(_stacks, starting_card_rank);
@@ -183,7 +184,7 @@ namespace Hanabi
       if (played_card.rank == 0 and _num_clues < max_num_clues)
       {
         // update clues if we played the last played_card of a stack
-        _num_clues++;
+        _num_clues += _clues_gained_on_discard_or_stack_finished;
       }
     }
 
@@ -209,7 +210,7 @@ namespace Hanabi
     ASSERT(_num_clues != max_num_clues);
 
     const Card discarded_card = _hands[_turn][index];
-    _num_clues++;
+    _num_clues += _clues_gained_on_discard_or_stack_finished;
     _pace--;
 
     unsigned long multiplicity = draw(index, cycle, false);
@@ -569,7 +570,7 @@ namespace Hanabi
     decr_turn();
     if (last_action.discarded.rank == 0 and not last_action.was_on_8_clues and not last_action.strike)
     {
-      _num_clues--;
+      _num_clues -= _clues_gained_on_discard_or_stack_finished;
     }
     revert_draw(last_action.index, last_action.discarded, cycle, !last_action.strike);
     if (not last_action.strike)
@@ -592,7 +593,7 @@ namespace Hanabi
     decr_turn();
     ASSERT(_num_clues > 0);
 
-    _num_clues--;
+    _num_clues -= _clues_gained_on_discard_or_stack_finished;
     _pace++;
 
     revert_draw(last_action.index, last_action.discarded, cycle, false);
@@ -650,8 +651,8 @@ namespace Hanabi
   template<suit_t num_suits, player_t num_players, hand_index_t hand_size>
   void HanabiState<num_suits, num_players, hand_size>::set_clues(Hanabi::clue_t clues)
   {
-    ASSERT(0 <= clues);
-    ASSERT(clues <= 8);
+    ASSERT(clue_t(0) <= clues);
+    ASSERT(clues <= clue_t(8));
     _num_clues = clues;
   }
 
@@ -764,6 +765,7 @@ namespace Hanabi
       }
     }
 
+    // Check for discards
     if (_pace > 0 and _num_clues < max_num_clues)
     {
       for (std::uint8_t index = 0; index < hand_size; index++)
@@ -1036,8 +1038,10 @@ namespace Hanabi
     }
 
     // encode number of clues
-    id *= max_num_clues + 1;
-    id += _num_clues;
+    clue_t const scaled_clues = clue_t(2) * _num_clues;
+    assert(scaled_clues.denominator() == 1);
+    id *= (max_num_clues * clue_t(2)).numerator() + 1;
+    id += scaled_clues.numerator();
 
     // we can encode draw pile size and extra turn in one metric, since we only have extra turns if draw pile is empty
     const std::uint8_t draw_pile_size_and_extra_turns = [this]() -> uint8_t {
@@ -1101,7 +1105,9 @@ namespace Hanabi
     }
 
     // encode number of clues
-    ret.push_back(_num_clues);
+    clue_t const scaled_clues = clue_t(2) * _num_clues;
+    assert(scaled_clues.denominator() == 1);
+    ret.push_back((clue_t(2) * _num_clues).numerator());
 
     // we can encode draw pile size and extra turn in one metric, since we only have extra turns if draw pile is empty
     const std::uint8_t draw_pile_size_and_extra_turns = [this]() -> uint8_t {

include/hanabi_types.hpp

@@ -13,7 +13,7 @@ namespace Hanabi
 
   using rank_t = std::uint8_t;
   using suit_t = std::uint8_t;
-  using clue_t = std::int8_t;
+  using clue_t = boost::rational<uint16_t>;
   using player_t = std::uint8_t;
   using hand_index_t = std::uint8_t;
 

src/command_line_interface.cpp

@@ -38,7 +38,7 @@ namespace Hanabi
     // We want to do this sanity check here again,
     // so that the run_cli method itself can ensure that arguments are fully valid
     // and we cannot run into crashes due to bad specified parameters
-    if (parms.recursive and std::holds_alternative<clue_t>(parms.clue_spec) and std::get<clue_t>(parms.clue_spec) != 0)
+    if (parms.recursive and std::holds_alternative<clue_t>(parms.clue_spec) and std::get<clue_t>(parms.clue_spec) != clue_t(0))
     {
       throw std::logic_error("Cannot use nonzero clue modifier together with recursive evaluation mode.");
     }
@@ -150,7 +150,7 @@ namespace Hanabi
           // When modifying the game state, we want to reset to the actual number of clues
           // to ensure that actions taken are legal.
           clue_t const original_num_clues = game.state->num_clues();
-          for (clue_t num_clues = 0; num_clues <= 8; num_clues++)
+          for (clue_t num_clues = 0; num_clues <= clue_t(8); num_clues++)
           {
             game.state->set_clues(num_clues);
             probability_t const result = game.state->evaluate_state();
@@ -304,7 +304,7 @@ namespace Hanabi
     parms.recursive = vm.count("recursive") > 0;
     parms.quiet = vm.count("quiet") > 0;
 
-    if (parms.recursive and std::holds_alternative<clue_t>(parms.clue_spec) and std::get<clue_t>(parms.clue_spec) != 0)
+    if (parms.recursive and std::holds_alternative<clue_t>(parms.clue_spec) and std::get<clue_t>(parms.clue_spec) != clue_t(0))
     {
       std::cout << "Conflicting options --recursive and --clue-modifier" << std::endl;
       std::cout << "Use '--help' to print a help message." << std::endl;

src/state_explorer.cpp

@@ -386,7 +386,7 @@ namespace Hanabi
 
       if (prompt.starts_with("clue"))
       {
-        if (game.state->num_clues() == 0)
+        if (game.state->num_clues() == clue_t(0))
         {
           std::cout << "You cannot give a clue at 0 clues." << std::endl;
           continue;