Merge pull request #1 from dharkness/add-xy-chains-solver

Add XY-Chain solver

README.md

@@ -1,3 +1,23 @@
 # Sudoku Rust
 
-Sudoku generator in Rust as a learning project.
+Sudoku generator, solver and player console application in Rust.
+
+[x] Learn Rust
+[x] Have fun
+[x] Generate new puzzles for my TypeScript Sudoku app
+
+## How to run
+
+To run the application,:
+
+1. Install Rust
+2. Clone the repository
+3. Run the application
+
+```bash
+cargo run
+```
+
+## Usage
+
+Once running, you'll be presented with the available commands.

src/play.rs

@@ -10,7 +10,7 @@ use crate::symbols::UNKNOWN_VALUE;
 
 const URL: &str = "https://www.sudokuwiki.org/sudoku.htm?bd=";
 
-const SOLVERS: [Solver; 18] = [
+const SOLVERS: [Solver; 19] = [
     crate::solvers::intersection_removals::find_intersection_removals,
     crate::solvers::naked_tuples::find_naked_pairs,
     crate::solvers::naked_tuples::find_naked_triples,
@@ -27,10 +27,11 @@ const SOLVERS: [Solver; 18] = [
     crate::solvers::xyz_wings::find_xyz_wings,
     crate::solvers::bugs::find_bugs,
     crate::solvers::avoidable_rectangles::find_avoidable_rectangles,
+    crate::solvers::xy_chains::find_xy_chains,
     crate::solvers::unique_rectangles::find_unique_rectangles,
     crate::solvers::empty_rectangles::find_empty_rectangles,
 ];
-const SOLVER_LABELS: [&str; 18] = [
+const SOLVER_LABELS: [&str; 19] = [
     "intersection removal",
     "naked pair",
     "naked triple",
@@ -47,6 +48,7 @@ const SOLVER_LABELS: [&str; 18] = [
     "xyz-wing",
     "bug",
     "avoidable rectangle",
+    "xy-chain",
     "unique rectangle",
     "empty rectangle",
 ];

src/puzzle/action.rs

@@ -40,6 +40,25 @@ impl Action {
         }
     }
 
+    pub fn new_erase_cells(strategy: Strategy, cells: CellSet, known: Known) -> Self {
+        Self {
+            strategy,
+            set: HashMap::new(),
+            erase: cells
+                .iter()
+                .map(|cell| (cell, KnownSet::empty() + known))
+                .collect(),
+        }
+    }
+
+    pub fn new_erase_knowns(strategy: Strategy, cell: Cell, knowns: KnownSet) -> Self {
+        Self {
+            strategy,
+            set: HashMap::new(),
+            erase: HashMap::from([(cell, knowns)]),
+        }
+    }
+
     pub fn is_empty(&self) -> bool {
         self.set.is_empty() && self.erase.is_empty()
     }

src/puzzle/effects.rs

@@ -69,6 +69,14 @@ impl Effects {
         self.add_action(Action::new_erase(strategy, cell, known));
     }
 
+    pub fn add_erase_cells(&mut self, strategy: Strategy, cells: CellSet, known: Known) {
+        self.add_action(Action::new_erase_cells(strategy, cells, known));
+    }
+
+    pub fn add_erase_knowns(&mut self, strategy: Strategy, cell: Cell, knowns: KnownSet) {
+        self.add_action(Action::new_erase_knowns(strategy, cell, knowns));
+    }
+
     pub fn erases(&self, cell: Cell, known: Known) -> bool {
         self.actions.iter().any(|action| action.erases(cell, known))
     }

src/puzzle/strategy.rs

@@ -87,6 +87,8 @@ pub enum Strategy {
     YWing,              // (Known, pivot Cell, arms (Cell, Cell))
     XYZWing,            // (Known, pivot Cell, arms (Cell, Cell))
 
-    EmptyRectangle, // (Known, Block, Row, Column, Cell) - CellSet instead of three houses
+    XYChain,         // (Known, Vec<Cell>)
     UniqueRectangle, // (Cell, Cell, Cell, Cell)
+
+    EmptyRectangle, // (Known, Block, Row, Column, Cell) - CellSet instead of three houses
 }

src/solvers.rs

@@ -14,6 +14,7 @@ pub mod naked_tuples;
 pub mod singles_chains;
 pub mod skyscrapers;
 pub mod unique_rectangles;
+pub mod xy_chains;
 pub mod xyz_wings;
 pub mod y_wings;