C++ - 从程序中删除函数

Question

我做了一个井字游戏程序，我使用一个函数来检查获胜或抽奖场景，代码运行良好，但我不允许在此任务中使用函数。

这是我现在的代码，添加 gameover() 函数后可以正常工作：

#include <iostream>
using namespace std;

bool gameover();   

char turn = 'X';
bool draw = false;
char board[3][3] = { { '1', '2', '3' }, { '4', '5', '6' }, { '7', '8', '9' } };

int main()
{   
    while (!gameover())
    {
        cout << "\nPlayer 1 [X] --- Player 2 [O]\n\n\n";
        cout << "\t" << board[0][0] << "   " << board[0][1] << "   " << board[0][2] << endl<< endl;
        cout << "\t" << board[1][0] << "   " << board[1][1] << "   " << board[1][2] << endl<< endl;
        cout << "\t" << board[2][0] << "   " << board[2][1] << "   " << board[2][2] << endl<< endl;
        int choice;
        int row = 0, column = 0;

        if (turn == 'X')
            cout << "Player 1 turn [X]: ";
        else if (turn == 'O')
            cout << "Player 2 turn [O]: ";

        cin >> choice;

        switch (choice)
        {
        case 1: row = 0; column = 0; break;
        case 2: row = 0; column = 1; break;
        case 3: row = 0; column = 2; break;
        case 4: row = 1; column = 0; break;
        case 5: row = 1; column = 1; break;
        case 6: row = 1; column = 2; break;
        case 7: row = 2; column = 0; break;
        case 8: row = 2; column = 1; break;
        case 9: row = 2; column = 2; break;
        default:
            cout << "\nYou didn't enter a correct number! Try again\n";
            continue;
        }

        if (turn == 'X' && board[row][column] != 'X' && board[row][column] != 'O')
        {
            board[row][column] = 'X';
            turn = 'O';
        }
        else if (turn == 'O' && board[row][column] != 'X' && board[row][column] != 'O')
        {
            board[row][column] = 'O';
            turn = 'X';
        }
        else
        {
            cout << "\nThe cell you chose is used! Try again\n";
            continue;
        }
        gameover();
    }

    if (turn == 'O' && !draw)
        cout << endl << endl << "Player 1 [X] Wins! Game Over!\n";
        else if (turn == 'X' && !draw)
            cout << endl << endl << "Player 2 [O] Wins! Game Over!\n";
        else
            cout << endl << endl << "It's a draw! Game Over!";

}

bool gameover()
{
    for (int i = 0; i < 3; i++)//Check for a win
        if ((board[i][0] == board[i][1] && board[i][1] == board[i][2]) || (board[0][i] == board[1][i] && board[1][i] == board[2][i]) || (board[0][0] == board[1][1] && board[1][1] == board[2][2]) || (board[0][2] == board[1][1] && board[1][1] == board[2][0]))
            return true;

    for (int i = 0; i < 3; i++)//Check for draw
        for (int j = 0; j < 3; j++)
            if (board[i][j] != 'X' && board[i][j] != 'O')
                return false;

    draw = true;
    return true;
}

但是当我删除gameover()函数并将其添加到int main()中时，它不检查win或draw，它一直显示显示板，程序没有结束。

我如何在 int main 中添加 gameover 函数并让它检查胜利或平局？

编辑：这是我到目前为止实现的代码，即使有 3 个直“X”，它仍然要求输出：

#include <iostream>
using namespace std;

bool gameover();   

char turn = 'X';
bool draw = false;
char board[3][3] = { { '1', '2', '3' }, { '4', '5', '6' }, { '7', '8', '9' } };

int main()
{   
    while (draw != true)
    {

        cout << "\nPlayer 1 [X] --- Player 2 [O]\n\n\n";
        cout << "\t" << board[0][0] << "   " << board[0][1] << "   " << board[0][2] << endl<< endl;
        cout << "\t" << board[1][0] << "   " << board[1][1] << "   " << board[1][2] << endl<< endl;
        cout << "\t" << board[2][0] << "   " << board[2][1] << "   " << board[2][2] << endl<< endl;
        int choice;
        int row = 0, column = 0;

        if (turn == 'X')
            cout << "Player 1 turn [X]: ";
        else if (turn == 'O')
            cout << "Player 2 turn [O]: ";

        cin >> choice;

        switch (choice)
        {
        case 1: row = 0; column = 0; break;
        case 2: row = 0; column = 1; break;
        case 3: row = 0; column = 2; break;
        case 4: row = 1; column = 0; break;
        case 5: row = 1; column = 1; break;
        case 6: row = 1; column = 2; break;
        case 7: row = 2; column = 0; break;
        case 8: row = 2; column = 1; break;
        case 9: row = 2; column = 2; break;
        default:
            cout << "\nYou didn't enter a correct number! Try again\n";
            continue;
        }

        if (turn == 'X' && board[row][column] != 'X' && board[row][column] != 'O')
        {
            board[row][column] = 'X';
            turn = 'O';
        }
        else if (turn == 'O' && board[row][column] != 'X' && board[row][column] != 'O')
        {
            board[row][column] = 'O';
            turn = 'X';
        }
        else
        {
            cout << "\nThe cell you chose is used! Try again\n";
            continue;
        }
        for (int i = 0; i < 3; i++)//Check for a win
        if ((board[i][0] == board[i][1] && board[i][1] == board[i][2]) || (board[0][i] == board[1][i] && board[1][i] == board[2][i]) || (board[0][0] == board[1][1] && board[1][1] == board[2][2]) || (board[0][2] == board[1][1] && board[1][1] == board[2][0]))
            draw = true;

        for (int i = 0; i < 3; i++)//Check for draw
            for (int j = 0; j < 3; j++)
                if (board[i][j] != 'X' && board[i][j] != 'O')
                    draw = false;
    }

    cout << "The Final Result\n\n\n";
    cout << "\t" << board[0][0] << "   " << board[0][1] << "   " << board[0][2] << endl<< endl;
    cout << "\t" << board[1][0] << "   " << board[1][1] << "   " << board[1][2] << endl<< endl;
    cout << "\t" << board[2][0] << "   " << board[2][1] << "   " << board[2][2] << endl<< endl;

    if (turn == 'O' && !draw)
        cout << endl << endl << "Player 1 [X] Wins! Game Over!\n";
        else if (turn == 'X' && !draw)
            cout << endl << endl << "Player 2 [O] Wins! Game Over!\n";
        else
            cout << endl << endl << "It's a draw! Game Over!";

}

bool gameover()
{
    for (int i = 0; i < 3; i++)//Check for a win
        if ((board[i][0] == board[i][1] && board[i][1] == board[i][2]) || (board[0][i] == board[1][i] && board[1][i] == board[2][i]) || (board[0][0] == board[1][1] && board[1][1] == board[2][2]) || (board[0][2] == board[1][1] && board[1][1] == board[2][0]))
            return true;

    for (int i = 0; i < 3; i++)//Check for draw
        for (int j = 0; j < 3; j++)
            if (board[i][j] != 'X' && board[i][j] != 'O')
                return false;

    draw = true;
    return true;
}

Answer 1

#include <iostream>

using namespace std;

char turn = 'X';
bool draw = false;
bool gameover = false;
char board[3][3] = { { '1', '2', '3' }, { '4', '5', '6' }, { '7', '8', '9' } };

int main()
{
    while (!gameover)
    {
        cout << "\nPlayer 1 [X] --- Player 2 [O]\n\n\n";
        cout << "\t" << board[0][0] << "   " << board[0][1] << "   " << board[0][2] << endl<< endl;
        cout << "\t" << board[1][0] << "   " << board[1][1] << "   " << board[1][2] << endl<< endl;
        cout << "\t" << board[2][0] << "   " << board[2][1] << "   " << board[2][2] << endl<< endl;
        int choice;
        int row = 0, column = 0;

        if (turn == 'X')
            cout << "Player 1 turn [X]: ";
        else if (turn == 'O')
            cout << "Player 2 turn [O]: ";

        cin >> choice;

        switch (choice)
        {
        case 1: row = 0; column = 0; break;
        case 2: row = 0; column = 1; break;
        case 3: row = 0; column = 2; break;
        case 4: row = 1; column = 0; break;
        case 5: row = 1; column = 1; break;
        case 6: row = 1; column = 2; break;
        case 7: row = 2; column = 0; break;
        case 8: row = 2; column = 1; break;
        case 9: row = 2; column = 2; break;
        default:
            cout << "\nYou didn't enter a correct number! Try again\n";
            continue;
        }

        if (turn == 'X' && board[row][column] != 'X' && board[row][column] != 'O')
        {
            board[row][column] = 'X';
            turn = 'O';
        }
        else if (turn == 'O' && board[row][column] != 'X' && board[row][column] != 'O')
        {
            board[row][column] = 'O';
            turn = 'X';
        }
        else
        {
            cout << "\nThe cell you chose is used! Try again\n";
            continue;
        }

        draw = true; //assume a draw
        for (int i = 0; i < 3; i++)//Check for a win
            if ((board[i][0] == board[i][1] && board[i][1] == board[i][2]) || (board[0][i] == board[1][i] && board[1][i] == board[2][i]) || (board[0][0] == board[1][1] && board[1][1] == board[2][2]) || (board[0][2] == board[1][1] && board[1][1] == board[2][0]))
            {
                gameover = true;
                draw = false;
                break;
            }

        if (!gameover)
            for (int i = 0; i < 3; i++)//Check for draw
                for (int j = 0; j < 3; j++)
                    if (board[i][j] != 'X' && board[i][j] != 'O')
                    {
                        draw = false;
                        break;
                    }

        if (draw)
            gameover = true;

    }

    if (turn == 'O' && !draw)
        cout << endl << endl << "Player 1 [X] Wins! Game Over!\n";
        else if (turn == 'X' && !draw)
            cout << endl << endl << "Player 2 [O] Wins! Game Over!\n";
        else
            cout << endl << endl << "It's a draw! Game Over!";

}

不太漂亮，但创建结构和可读性是函数的用途。

Answer 2

修改后的代码有两个问题，一个算法，一个领域。

算法错误是return 语句终止函数的执行。这意味着不会对该函数体进行进一步处理。

在您修改后的代码中，不会发生这样的控制流中断——两个for 循环都会完整执行。这意味着在板子满之前，第二个for 循环会将draw 重置为false，即使前一个将其设置为true。

第二个域问题是您错误地重新使用了draw 变量。以前，它的意思是“比赛是否以平局结束？”现在，您将其用作“游戏结束了吗？”为此，您需要两个单独的变量。

进行这些更改后，代码看起来很像@user1320881's answer。