根據布爾值無法結束do/while循環 - C++

Question

已修復。謝謝。

在我的代碼下面，它編譯並運行，但卡在do/while循環中。返回值正在工作，但while循環一定不能識別它，它會無限期地運行。我可以收到真假的回報;都不停止循環。真的迷失在這裏，找不到答案。謝謝。

//helper function for inputGuess 
//checks if the user's guess is in the lowercase alphabet and that 
// it has not been guessed before 
bool Hangman::validGuess() { 
    //checks if the character guess is in the lowercase alphabet 
    if (guess >= 97 && guess <= 122) { 
    //checks if the user's guess has been guessed previously 
    if (guessed.size() > 0) { 
     for (int i = 0; i < guessed.size(); i++) { 
     cout << "enter for\n"; 
     cout << "guess[i]: " << guessed[i] << endl; 
     if (guess != guessed[i]) { 
      cout << "1st true: guess has not been guessed\n"; 
      return true; 
     } 
     else { 
      cout << "1st false: same letter\n"; 
      return false; 
     } 
     } 
    } 
    else { 
     cout << "2nd true: guessed size is 0\n"; 
     return true; 
    } 
    } 
    else { 
    cout << "2nd false: not alphabet\n"; 
    return false; 
    } 
} 

//gets input for guess, checks if guess is valid, adds guess to guessed 
void Hangman::inputGuess() { 
    bool valid = false; 
    do { 
    cout << "Please enter your guess: "; 
    cin >> guess; 
    cout << endl; 
    valid = validGuess(); 
    cout << "valid: " << valid << endl; 
    } while (valid == false); 
    guessed.push_back(guess); 
} 

Answer 1

當guessed爲空時，您有一個未定義的返回事件，因爲它已經過去並且沒有默認返回。

無論如何，這段代碼看起來過於複雜。像這樣的東西可能會更好：

bool HangMan::validGuess() { 
    //checks if the character guess is in the lowercase alphabet 
    if (isalpha(guess)) { 
     //checks if the user's guess has been guessed previously 
     if (find(guessed.begin(), guessed.end(), guess) != guessed.end()) { 
      cout << "1st false: same letter\n"; 
      return false; 
     } 
     else { 
      cout << "1st true: guess has not been guessed\n"; 
      return true; 
     } 
    } else { 
     cout << "2nd false: not alphabet\n"; 
     return false; 
    } 
} 

Answer 2

你應該將guess作爲參數傳遞給validGuess（）這就是你的問題。嘗試加入

this->guess 

而不是隻是猜測。