c++ - 生成超出我的范围C++的数字(太大)

我决定尝试制作一个简单的程序，以“笨拙”的方式模拟二十一点。除了随机生成的数字太大以外，基本上已经完成了。我不关心rand / rand的偏见(目前)，我只是想使其正常工作。

#include <iostream>
#include <cstdlib>
#include <cmath>
#include <ctime>

using namespace std;

int genRandInt (int low, int high) {
    int randnum = low + (rand() % (high - low + 1));
    return randnum;
}

int main()
{
    srand(time(NULL));
    int computerScore;
    int score;
    int card;

    while (int playAgain = 1)
    {
        cout << "Enter 0 to hold or 1 to hit: ";
        int play;
        cin >> play;

        if (play == 0)
        {
             computerScore = genRandInt(1, 31);

             if (score < computerScore)
             {
                 cout << "Your score is " << score << " and the computer's score is " << computerScore << "! You lose.\n";
             }

             if (score > 21)
             {
                 cout << "Your score is " << score << " which is greater than 21. Bust!\n";
             }

             if (score > computerScore && score <= 21)
             {
                 cout << "Your score is " << score << " and the computer's score is " << computerScore << "! You win!\n";
             }

             cout << "Would you like to play again? 1 for yes, 0 for no. : ";
             cin >> playAgain;
        }


        if (play == 1)
        {
            card = genRandInt(1, 11);
            score = score + card;
            cout << "Your score is: " << score << "\n";
        }
    }



    return 0;
}

有任何想法吗？

最佳答案

您使用未初始化的int score;

if (score < computerScore)

要么

score = score + card;

取决于if(play == 0)或if(play == 1)条件。

它的内存内容恰好有一些垃圾，编译器不会为您初始化零。实际上，使用未初始化的变量是未定义的行为。在首次使用之前初始化它，最好在定义本身中使用，

int score = 0;

另外，请在上加上警告(对于g++ / clang++为-Wall -Wextra)进行编译，因为编译器很容易就这些错误发出警告。