c++ - While 在 C++ 中使用定时器循环

Question

我正在尝试创建一个 while 循环，当满足字符串条件或计时器条件时，程序将跳出循环并打印出所需的输出。并且在打印出所需的输出时，输出将包含比较答案前后的时间差。

但是循环没有按照我期望的方式运行。那么谁能帮我找出这段代码的问题在哪里？

下面是我的代码:

void startGame(time_t cd,int gl){
    string guessWord;
    time_t start, end, diff,timeLeft;

    cout << "Scrambled word is " << randomizeWord(gl) << endl;

    while (timeLeft != cd || guessWord.compare(originalWord) == 0)
    {
        start = time(0);
        cout << "You have " << cd << " seconds to guess." << endl;
        cout << "Enter guess : ";
        cin >> guessWord;
        end = time(0);
        diff = end - start;
        //total_time = total_time + diff;
        timeLeft = cd - diff;

        if(guessWord.compare(originalWord) != 0)
        {
            cout << "WRONG! Attempt ... You have " << timeLeft << "seconds left... Try Again" << endl;
            cout << "Enter guess : ";
            cin >> guessWord;             
        }
        else
        {
            cout << "You are CORRECT! "<< timeLeft <<" seconds left. Your timing is "<< diff <<" seconds." << endl;            
            break;
        }
    }
}

Answer 1

条件说明

也改变你的循环条件:

while ((timeLeft <= cd) && (guessWord.compare(originalWord) != 0))

如果其中一个条件失败，你就会爆发。这是因为如果任一条件失败，&& 的结果为 false。所以这将继续，而 a) 您还有时间并且 b) 您还没有猜到这个词。您对 || 的使用将使循环继续，而其中一个为真(因此两者都必须失败才能退出循环)。

注意:我个人认为额外的大括号 () 很适合让表达式更易于阅读。对于没有经验的程序员，他们不需要猜测(查找)优先顺序

剩余时间计算:

time_t start    = time(0);  // Make the start time absolute and outside the loop.
                            // Note: Use one line per variable declaration and initialize.
int    timeLeft = cd;       // timeLeft is a relative value that can be negative => `int`

// Notice I adjust timeLeft because of new definition.
while ((timeLeft > 0) && (guessWord.compare(originalWord) != 0))
{
    time_t end       = time(0);
    time_t timeTaken = end-start;        // Total time taken so Far.
    timeLeft         = cd - timeTaken;   // Time left is thus.