Fixes Bug of not identifying characters which are not part of the word

src/game.cpp

@@ -21,7 +21,7 @@ GameState::guess(const std::string &guessedWord) {
   for (std::string::size_type i = 0; i < guessedWord.size(); i++) {
     if (word[i] == guessedWord[i]) {
       matchStatus[i] = EXACT_MATCH;
-    } else if (word.find(guessedWord[i])) {
+    } else if (word.find(guessedWord[i]) != std::string::npos) {
       matchStatus[i] = MATCH;
     } else {
       matchStatus[i] = NO_MATCH;