Question

How to write a (c++ program) tic tac toe code where its the computer against a human. and the computer always wins.

a basic c++ code program
using gaming theory
arrays
<stdio.h>

computer plays tic tac toe against a user.
computer always when or the game is a draw.

Answer 1

/* Program in c++ */

#include <iostream>
#include <ctime>
#include <cstdio>
#include <cstdlib>

using namespace std;

bool TurnPlayer;
int gameWin = 3;
int ComputerRandomPosition; //random pick computer position
int computerPick; //decide term
int Choice_Of_The_player;

//board for tic tac toe arrays
char block1 = '1';
char block2 = '2';
char block3 = '3';
char block4 = '4';
char block5 = '5';
char block6 = '6';
char block7 = '7';
char block8 = '8';
char block9 = '9';
int Firstturn; //variable to decide whoever goes first
//check the all codition for win
int CheckComputerWin()
{
    if(block1 == 'O' && block5 == 'O' && block9 == 'O' && TurnPlayer == false)
        gameWin = 2;
    if(block3 == 'O' && block5 == 'O' && block7 == 'O' && TurnPlayer == false)
        gameWin = 2;
    if(block1 == 'O' && block2 == 'O' && block3 == 'O' && TurnPlayer == false)
        gameWin = 2;
    if(block4 == 'O' && block5 == 'O' && block6 == 'O' && TurnPlayer == false)
        gameWin = 2;
    if(block7 == 'O' && block8 == 'O' && block9 == 'O' && TurnPlayer == false)
        gameWin = 2;
    if(block1 == 'O' && block4 == 'O' && block7 == 'O' && TurnPlayer == false)
        gameWin = 2;
    if(block2 == 'O' && block5 == 'O' && block8 == 'O' && TurnPlayer == false)
        gameWin = 2;
    if(block3 == 'O' && block6 == 'O' && block9 == 'O' && TurnPlayer == false)
        gameWin = 2;
}
int checkWinPlayer()
{
    if(block1 == 'X' && block5 == 'X' && block9 == 'X' && TurnPlayer == true) //diagonal, 1 - 5 = 9
        gameWin = 1; //This will make player win.
    if(block3 == 'X' && block5 == 'X' && block7 == 'X' && TurnPlayer == true) //diagonal, 3 - 5 = 7
        gameWin = 1;
    if(block1 == 'X' && block2 == 'X' && block3 == 'X' && TurnPlayer == true) //horizontal 1 - 2 = 3
        gameWin = 1;
    if(block4 == 'X' && block5 == 'X' && block6 == 'X' && TurnPlayer == true) //horizontal 4 - 5 = 6
        gameWin = 1;
    if(block7 == 'X' && block8 == 'X' && block9 == 'X' && TurnPlayer == true) //horizontal 7 - 8 = 9
        gameWin = 1;
    if(block1 == 'X' && block4 == 'X' && block7 == 'X' && TurnPlayer == true) //vertical 1 - 4 = 7
        gameWin = 1;
    if(block2 == 'X' && block5 == 'X' && block8 == 'X' && TurnPlayer == true) //vertical 2 - 5 = 8
        gameWin = 1;
    if(block3 == 'X' && block6 == 'X' && block9 == 'X' && TurnPlayer == true) //vertical 3 - 6 = 9
        gameWin = 1;
}
int ArtificalComputer()
{
    TurnPlayer == false;

    if(block1 == 'O' && block2 == 'O' && TurnPlayer == false && block3 == '3')
    {
        block3 = 'O';
        TurnPlayer = true;
    }

    if(block4 == 'O' && block5 == 'O' && TurnPlayer == false && block6 == '6')
    {
        block6 = 'O';
        TurnPlayer = true;
    }

    if(block7 == 'O' && block8 == 'O' && TurnPlayer == false && block9 == '9')
    {
        block9 = 'O';
        TurnPlayer = true;
    }

    if(block1 == 'O' && block4 == 'O' && TurnPlayer == false && block7 == '7')
    {
        block7 = 'O';
        TurnPlayer = true;
    }

    if(block2 == 'O' && block5 == 'O' && TurnPlayer == false && block8 == '8')
    {
        block8 = 'O';
        TurnPlayer = true;
    }

    if(block3 == 'O' && block6 == 'O' && TurnPlayer == false && block9 == '9')
    {
        block9 = 'O';
        TurnPlayer = true;
    }

    if(block1 == 'O' && block5 == 'O' && TurnPlayer == false && block9 == '9')
    {
        block9 = 'O';
        TurnPlayer = true;
    }

    if(block3 == 'O' && block5 == 'O' && TurnPlayer == false && block7 == '7')
    {
        block7 = 'O';
        TurnPlayer == true;
    }

    if((Choice_Of_The_player == 1 || Choice_Of_The_player == 5 || Choice_Of_The_player == 9) && TurnPlayer == false)
    {
        if((block1 == 'X' && block5 == 'X') && TurnPlayer == false && block9 == '9')
        {
            block9 = 'O';
            TurnPlayer = true;
        }

        if((block1 == 'X' && block9 == 'X') && TurnPlayer == false && block5 == '5')
        {
            block5 = 'O';
            TurnPlayer = true;
        }

        if((block5 == 'X' && block9 == 'X') && TurnPlayer == false && block1 == '1')
        {
            block1 = 'O';
            TurnPlayer = true;
        }
    }

    if((Choice_Of_The_player == 3 || Choice_Of_The_player == 5 || Choice_Of_The_player == 7) && TurnPlayer == false)
    {
        if((block7 == 'X' && block5 == 'X') && TurnPlayer == false && block3 == '3')
        {
            block3 = 'O';
            TurnPlayer = true;
        }

        if((block7 == 'X' && block3 == 'X') && TurnPlayer == false && block5 == '5')
        {
            block5 = 'O';
            TurnPlayer = true;
        }

        if((block5 == 'X' && block3 == 'X') && TurnPlayer == false && block7 == '7')
        {
            block7 = 'O';
            TurnPlayer = true;
        }
    }

    if((Choice_Of_The_player == 1 || Choice_Of_The_player == 2 || Choice_Of_The_player == 3) && TurnPlayer == false)
    {
        if((block1 == 'X' && block2 == 'X') && TurnPlayer == false && block3 == '3')
        {
            block3 = 'O';
            TurnPlayer = true;
        }

        if((block1 == 'X' && block3 == 'X') && TurnPlayer == false && block2 == '2')
        {
            block2 = 'O';
            TurnPlayer = true;
        }

        if((block2 == 'X' && block3 == 'X') && TurnPlayer == false && block1 == '1')
        {
            block1 = 'O';
            TurnPlayer = true;
        }
    }

    if((Choice_Of_The_player == 4 || Choice_Of_The_player == 5 || Choice_Of_The_player == 6) && TurnPlayer == false)
    {
        if((block4 == 'X' && block5 == 'X') && TurnPlayer == false && block6 == '6')
        {
            block6 = 'O';
            TurnPlayer = true;
        }

        if((block4 == 'X' && block6 == 'X') && TurnPlayer == false && block5 == '5')
        {
            block5 = 'O';
            TurnPlayer = true;
        }

        if((block5 == 'X' && block6 == 'X') && TurnPlayer == false && block4 == '4')
        {
            block4 = 'O';
            TurnPlayer = true;
        }
    }

    if((Choice_Of_The_player == 7 || Choice_Of_The_player == 8 || Choice_Of_The_player == 9) && TurnPlayer == false)
    {
        if((block7 == 'X' && block8 == 'X') && TurnPlayer == false && block9 == '9')
        {
            block9 = 'O';
            TurnPlayer = true;
        }

        if((block7 == 'X' && block9 == 'X') && TurnPlayer == false && block8 == '8')
        {
            block8 = 'O';
            TurnPlayer = true;
        }

        if((block8 == 'X' && block9 == 'X') && TurnPlayer == false && block7 == '7')
        {
            block7 = 'O';
            TurnPlayer = true;
        }
    }

    if((Choice_Of_The_player == 1 || Choice_Of_The_player == 4 || Choice_Of_The_player == 7) && TurnPlayer == false)
    {
        if((block1 == 'X' && block4 == 'X') && TurnPlayer == false && block7 == '7')
        {
            block7 = 'O';
            TurnPlayer = true;
        }

        if((block1 == 'X' && block7 == 'X') && TurnPlayer == false && block4 == '4')
        {
            block4 = 'O';
            TurnPlayer = true;
        }

        if((block4 == 'X' && block7 == 'X') && TurnPlayer == false && block1 == '1')
        {
            block1 = 'O';
            TurnPlayer = true;
        }

    }

    if((Choice_Of_The_player == 2 || Choice_Of_The_player == 5 || Choice_Of_The_player == 8) && TurnPlayer == false)
    {
        if((block2 == 'X' && block5 == 'X') && TurnPlayer == false && block8 == '8')
        {
            block8 = 'O';
            TurnPlayer = true;
        }

        if((block2 == 'X' && block8 == 'X') && TurnPlayer == false && block5 == '5')
        {
            block5 = 'O';
            TurnPlayer = true;
        }

        if((block5 == 'X' && block8 == 'X') && TurnPlayer == false && block2 == '2')
        {
            block2 = 'O';
            TurnPlayer = true;
        }
    }

    if((Choice_Of_The_player == 3 || Choice_Of_The_player == 6 || Choice_Of_The_player == 9) && TurnPlayer == false)
    {
        if((block3 == 'X' && block6 == 'X') && TurnPlayer == false && block9 == '9')
        {
            block9 = 'O';
            TurnPlayer = true;
        }

        if((block3 == 'X' && block9 == 'X') && TurnPlayer == false && block6 == '6')
        {
            block6 = 'O';
            TurnPlayer = true;
        }

        if((block6 == 'X' && block9 == 'X') && TurnPlayer == false && block3 == '3')
        {
            block3 = 'O';
            TurnPlayer = true;
        }
    }
    else
    {
        do
        {

            if(block1 == '1' && TurnPlayer == false)
            {
                TurnPlayer = true;
                block1 = 'O';
            }
            if(block2 == '2' && TurnPlayer == false)
            {
                TurnPlayer = true;
                block2 = 'O';
            }
            if(block3 == '3' && TurnPlayer == false)
            {
                TurnPlayer = true;
                block3 = 'O';
            }
            if(block4 == '4' && TurnPlayer == false)
            {
                TurnPlayer = true;
                block4 = 'O';
            }
            if(block5 == '5' && TurnPlayer == false)
            {
                TurnPlayer = true;
                block5 = 'O';
            }
            if(block6 == '6' && TurnPlayer == false)
            {
                TurnPlayer = true;
                block6 = 'O';
            }
            if(block7 == '7' && TurnPlayer == false)
            {
                TurnPlayer = true;
                block7 = 'O';
            }
            if(block8 == '8' && TurnPlayer == false)
            {
                TurnPlayer = true;
                block8 = 'O';
            }
            if(block9 == '9' && TurnPlayer == false)
            {
                TurnPlayer = true;
                block9 = 'O';
            }
        }
        while(TurnPlayer = false);
    }
    return 0;
}

int checkPlayerInput()
{
    if(Choice_Of_The_player == 1 && block1 == '1')
        block1 = 'X';
    if(Choice_Of_The_player == 2 && block2 == '2')
        block2 = 'X';
    if(Choice_Of_The_player == 3 && block3 == '3')
        block3 = 'X';
    if(Choice_Of_The_player == 4 && block4 == '4')
        block4 = 'X';
    if(Choice_Of_The_player == 5 && block5 == '5')
        block5 = 'X';
    if(Choice_Of_The_player == 6 && block6 == '6')
        block6 = 'X';
    if(Choice_Of_The_player == 7 && block7 == '7')
        block7 = 'X';
    if(Choice_Of_The_player == 8 && block8 == '8')
        block8 = 'X';
    if(Choice_Of_The_player == 9 && block9 == '9')
        block9 = 'X';

    return 0;
}

int checkComputerInput()
{
    if(computerPick == 1 && block1 == '1')
        block1 = 'O';
    if(computerPick == 2 && block2 == '2')
        block2 = 'O';
    if(computerPick == 3 && block3 == '3')
        block3 = 'O';
    if(computerPick == 4 && block4 == '4')
        block4 = 'O';
    if(computerPick == 5 && block5 == '5')
        block5 = 'O';
    if(computerPick == 6 && block6 == '6')
        block6 = 'O';
    if(computerPick == 7 && block7 == '7')
        block7 = 'O';
    if(computerPick == 8 && block8 == '8')
        block8 = 'O';
    if(computerPick == 9 && block9 == '9')
        block9 = 'O';

    return 0;
}

void Borad_of_GAME()
{
    cout << "+-----+-----+-----+" << endl;
    cout << "| " <<block1 << " | " << block2 << " | " << block3 << " |" << endl;
    cout << "+-----+-----+-----+" << endl;
    cout << "| " <<block4 << " | " << block5 << " | " << block6 << " |" << endl;
    cout << "+-----+-----+-----+" << endl;
    cout << "| " <<block7 << " | " << block8 << " | " << block9 << " |\n";
    cout << "+-----+-----+-----+" << endl;
}

int checkTie()
{
    if(block1 != '1' && block2 != '2' && block3 != '3' && block4 != '4' && block5 != '5' && block6 != '6' && block7 != '7' && block8 != '8' && block9 != '9')
    {
        cout << "It's a tie!" << endl;
        gameWin = 0;
    }
//Check on this line since it doesnt work..

}

int main()
{
    //RNGs
    srand(time(0));
    int playAgain;

    int playerScore = 0;
    int computerScore = 0;
    int ties = 0;

    do
    {
        system("CLS");
        Firstturn = rand()% (2 - 1 + 1)+1;//generates starting person.
        ComputerRandomPosition = rand()% (9 - 1 + 1)+1;//computer first pick - random
        gameWin = 3;
        block1 = '1';
        block2 = '2';
        block3 = '3';
        block4 = '4';
        block5 = '5';
        block6 = '6';
        block7 = '7';
        block8 = '8';
        block9 = '9';

        //start OF PROGRAM
        cout << "Welcome to Tic Tac Toe Game" <<endl<< endl;
        cout << "Player: " << playerScore << " Computer: "<< computerScore << " Ties: " << ties << endl;

        if(Firstturn == 1)//player first
        {
            cout << "Please Select your a grid to place (X): "<<endl<<endl;
            Borad_of_GAME();//Borad_of_GAME for tic tac toe
            while (!(cin >> Choice_Of_The_player)) //error traps letters and words
            {
                cout << endl;
                cout << "Numbers only." << endl;
               // cin.clear();
                //cin.ignore(10000,'\n');
            }
            checkPlayerInput();
           // system("CLS");
            Borad_of_GAME();
            TurnPlayer = false; //switches to computer
        }

        if(Firstturn == 2)//Computer first
        {
            ComputerRandomPosition;
            computerPick = ComputerRandomPosition;
            checkComputerInput();
            cout << "The computer is choosing...\n" << endl;
            TurnPlayer = true;
            Borad_of_GAME();
        }

        do
        {
            if(TurnPlayer == true) //player loop
            {
                cout << "Please choose a grid to place (X): "<<endl<<endl;
                while (!(cin >> Choice_Of_The_player)) //error traps letters and words
                {
                    cout << endl;
                    cout << "Numbers only." << endl;
                    cin.clear();
                    cin.ignore(10000,'\n');
                }
                checkPlayerInput();
                checkWinPlayer();
                checkTie();
                TurnPlayer = false;
            }

            if(TurnPlayer == false) //computer loop
            {
                ArtificalComputer();
                Borad_of_GAME();
                CheckComputerWin();
                checkTie();
                TurnPlayer = true;
            }

        }
        while(gameWin > 2);

        if(gameWin == 0)
        {
            cout << "The game is a Tie!" << endl;
            ++ties;
        }

        if(gameWin == 1)
        {
            cout << "The player wins!" << endl;
            ++playerScore;
        }

        if(gameWin == 2)
        {
            cout << "The computer wins!" << endl;
            ++computerScore;
        }

        cout << "Player: " << playerScore << " "<< "Computer: " << computerScore << " Ties: "<< ties << endl;

        cout << "Play again?\n1. Yes\n2. No\n" << endl;

        while (!(cin >> playAgain)) //error traps letters and words
        {
            cout << endl;
            cout << "Play again?\n1. Yes\n2. No\n" << endl;
            cin.clear();
            cin.ignore(10000,'\n');
        }

    }
    while(playAgain == 1);

    return 0;
}

/*

Welcome to Tic Tac Toe Game

Player: 0 Computer: 0 Ties: 0
The computer is choosing...

+-----+-----+-----+
| 1 | 2 | O |
+-----+-----+-----+
| 4 | 5 | 6 |
+-----+-----+-----+
| 7 | 8 | 9 |
+-----+-----+-----+
Please choose a grid to place (X):

1
+-----+-----+-----+
| X | O | O |
+-----+-----+-----+
| 4 | 5 | 6 |
+-----+-----+-----+
| 7 | 8 | 9 |
+-----+-----+-----+
Please choose a grid to place (X):

3
+-----+-----+-----+
| X | O | O |
+-----+-----+-----+
| 4 | 5 | 6 |
+-----+-----+-----+
| 7 | 8 | 9 |
+-----+-----+-----+
Please choose a grid to place (X):

5
+-----+-----+-----+
| X | O | O |
+-----+-----+-----+
| 4 | X | 6 |
+-----+-----+-----+
| 7 | 8 | O |
+-----+-----+-----+
Please choose a grid to place (X):

9
+-----+-----+-----+
| X | O | O |
+-----+-----+-----+
| 4 | X | 6 |
+-----+-----+-----+
| 7 | 8 | O |
+-----+-----+-----+
Please choose a grid to place (X):

6
+-----+-----+-----+
| X | O | O |
+-----+-----+-----+
| O | X | X |
+-----+-----+-----+
| 7 | 8 | O |
+-----+-----+-----+
Please choose a grid to place (X):

7
+-----+-----+-----+
| X | O | O |
+-----+-----+-----+
| O | X | X |
+-----+-----+-----+
| X | O | O |
+-----+-----+-----+
It's a tie!
The game is a Tie!
Player: 0 Computer: 0 Ties: 1
Play again?
1. Yes
2. No

*/