C++随机数猜测游戏-变量未声明错误

Question

所以我必须创建一个随机数猜测游戏。我知道还有其他类似的问题，但如果有人能给我指明正确的方向，我将不胜感激。我对C++很陌生。

我的问题似乎是，在每个难度函数中都没有提取变量。我得到了未声明的错误。

非常感谢。

#include <iostream>
#include <cstdlib>
#include <ctime>
using namespace std;
int easy()
{
    srand(seed);
    randomNumber = 1 + rand() %12;
    cout << "I am thinking of a number between 1 and 12. Can you guess what it is?" << endl;
    cout << randomNumber << endl;
    cin >> userNumber;
    while (!win)
    {
        if (userNumber < randomNumber)
        {
            numOfAttempts++;
            cout << "Attempt " << numOfAttempts << ". " << userNumber << " is too low. Please try again" << endl;
            cin >> userNumber;
            playerScore -= 5;
        }
        else if (userNumber > randomNumber)
        {
            numOfAttempts++;
            cout << "Attempt " << numOfAttempts << ". " << userNumber << " is too high. Please try again" << endl;
            cin >> userNumber;
            playerScore -= 5;
        }
        else
        {
            numOfAttempts++;
            cout << "Congratulations. You guessed the correct number. It took you " << numOfAttempts << " attempts." << endl;
            cout << "Your score is " << playerScore << endl;
            win = true;
        }
    }
}
int medium()
{
    srand(seed);
    randomNumber = 1 + rand() %30;
    cout << "I am thinking of a number between 1 and 30. Can you guess what it is?" << endl;
    cout << randomNumber << endl;
    cin >> userNumber;
    while (!win)
    {
        if (userNumber < randomNumber)
        {
            numOfAttempts++;
            cout << "Attempt " << numOfAttempts << ". " << userNumber << " is too low. Please try again" << endl;
            cin >> userNumber;
            playerScore -= 5;
        }
        else if (userNumber > randomNumber)
        {
            numOfAttempts++;
            cout << "Attempt " << numOfAttempts << ". " << userNumber << " is too high. Please try again" << endl;
            cin >> userNumber;
            playerScore -= 5;
        }
        else
        {
            numOfAttempts++;
            cout << "Congratulations. You guessed the correct number. It took you " << numOfAttempts << " attempts." << endl;
            cout << "Your score is " << playerScore << endl;
            win = true;
        }
    }
}
int hard()
{
    srand(seed);
    randomNumber = 1 + rand() %50;
    cout << "I am thinking of a number between 1 and 50. Can you guess what it is?" << endl;
    cout << randomNumber << endl;
    cin >> userNumber;
    while (!win)
    {
        if (userNumber < randomNumber)
        {
            numOfAttempts++;
            cout << "Attempt " << numOfAttempts << ". " << userNumber << " is too low. Please try again" << endl;
            cin >> userNumber;
            playerScore -= 5;
        }
        else if (userNumber > randomNumber)
        {
            numOfAttempts++;
            cout << "Attempt " << numOfAttempts << ". " << userNumber << " is too high. Please try again" << endl;
            cin >> userNumber;
            playerScore -= 5;
        }
        else
        {
            numOfAttempts++;
            cout << "Congratulations. You guessed the correct number. It took you " << numOfAttempts << " attempts." << endl;
            cout << "Your score is " << playerScore << endl;
            win = true;
        }
    }
}
int main ()
{
public:
    int randomNumber;
    int userNumber;
    bool win = false;
    unsigned seed = time(0);
    int numOfAttempts = 0;
    int playerScore = 50;
    int difficulty;
    cout << "Please choose a difficulty. 1 = easy, 2 = medium, 3 = hard." << endl;
    cin >> difficulty;
    switch(difficulty)
    {
    case 1:
        cout << "You have chosen EASY!" << endl;
        easy();
        break;
    case 2:
        cout << "You have chosen MEDIUM!" << endl;
        medium();
        break;
    case 3:
        cout << "You have chosen HARD!" << endl;
        hard();
        break;
    default:
        cout << "You are playing EASY!" << endl;
        easy();
        break;
    }
    return 0;
}

Answer 1

您的问题是您在困难函数中使用的变量没有在这些函数中声明。您应该将它们作为参数传递给这些函数

int hard(int randomNumber, unsigned seed)

Answer 2

错误消息非常清楚。例如，变量randomNumber的声明在哪里？

#include <iostream>
#include <cstdlib>
#include <ctime>
using namespace std;
int easy()
{
    srand(seed);
    randomNumber = 1 + rand() %12;
    ^^^^^^^^^^^^
//...

或者这意味着什么？

int main ()
{
public:
    int randomNumber;
    int userNumber;
    bool win = false;
    unsigned seed = time(0);
    int numOfAttempts = 0;
    int playerScore = 50;
    int difficulty;
//...

从语法角度来看，该代码无效。你应该纠正它。

Answer 3

通常，错误代码会给您提供相当多的信息（直到您进入模板编码，才有另一条学习曲线）。你的代码有很多错误，甚至在没有为你做所有工作的情况下就开始帮助你。

请复制并粘贴更好地描述实际的错误/警告消息，并不是所有人都有编译器在工作，以了解发生了什么。