add panic if solution space is empty

src/app/wordle_simulation.rs

@@ -5,7 +5,9 @@ use wordle_solver::{game::Game, solver::Solver, word_list::WordList};
 pub fn main() {
     let valid_words = WordList::from_file(Path::new("valid-words.txt")).unwrap();
     let target_words = WordList::from_file(Path::new("answers.txt")).unwrap();
-    let mut game = Game::new(target_words.random_word());
+    let target_word = target_words.random_word();
+    println!("Target: {}", target_word);
+    let mut game = Game::new(target_word);
 
     let mut solver = Solver::new(valid_words, target_words);
 

src/lib/solver.rs

@@ -58,6 +58,10 @@ impl Solver {
         let information_gained = self.possible_solutions.equal_likelieness_entropy()
             - new_possible_solutions.equal_likelieness_entropy();
 
+        if new_possible_solutions.len() == 0 {
+            panic!("Solution space is empty");
+        }
+
         self.possible_solutions = new_possible_solutions;
 
         self.guesses.push(Guess {