The first thing I had to do was workout what the best way to put together the game would be. I know there are plenty of ways in which to complete this project but first I thought about the vairables I would need. The board itself, an introduction, check if the board is filled, check if a player has won, etc.

I checked that each function would work, and wrote a comment to myself next the function so I can keep track of which ones I had checked.

    #include <iostream>
    #include <vector>

    // Create vector for board
    std::vector<std::vector<char>> board {
        {'0','1','2'}, 
        {'3','4','5'}, 
        {'6','7','8'}};

    // Variable to track player moves for each turn
    int current_player = 1;
    std::vector<int> move;

    // Declare functions to track game status
    bool is_winner(); //works
    bool filled_up(); //works
    void introduction(); //works
    void take_turn(); //works
    void set_position(); //works
    void update_board(); //works
    void change_player(); //works
    void draw(); //works
    void end_game(); //works

            

Next was to start creating the functions in order for the game to, well, function. I made many mistakes in the functions and when I checked if they worked it didn't always work first time. According to Codecademy, they said the project would take 36 minutes, however it was looking more like 5 hours for myself, and while that is a ridiculous amount of time for such a small project, it was a massive learning curve for me and I feel like my programming and understanding has improved immensely because of it.

In the function file, I was sure to include the ttt.hpp file so that they could link to the predeclared functions and variables.

    #include <iostream>
    #include <vector>
    #include "ttt.hpp"

    // Introduction
    void introduction() {
        std::cout << "\n  Welcome to Tic Tac Toe!\n";
        std::cout << "____________________________\n\n";
        std::cout << "Player 1 is X and Player 2 is O\n";
        std::cout << "The board positions are numbered as follows:\n\n";
        draw();
        std::cout << "Let the game begin!\n";
    }

    // Create board to play Tic Tac Toe
    void draw() {
        std::cout << " " << board[0][0] << " | " << board[0][1] << " | " << board[0][2] << " \n";
        std::cout << "___________\n";
        std::cout << " " << board[1][0] << " | " << board[1][1] << " | " << board[1][2] << " \n";
        std::cout << "___________\n";
        std::cout << " " << board[2][0] << " | " << board[2][1] << " | " << board[2][2] << " \n\n";
    }

    // Function to check for a win
    bool is_winner() {
        // Check rows, columns, and diagonals
        if ((board[0][0] == board[0][1] && board[0][1] == board[0][2]) ||
            (board[1][0] == board[1][1] && board[1][1] == board[1][2]) ||
            (board[2][0] == board[2][1] && board[2][1] == board[2][2]) ||
            (board[0][0] == board[1][0] && board[1][0] == board[2][0]) ||
            (board[0][1] == board[1][1] && board[1][1] == board[2][1]) ||
            (board[0][2] == board[1][2] && board[1][2] == board[2][2]) ||
            (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;
            ;
        }
        return false;
    }

    // Function to check if board is filled up
    bool filled_up() {
        for(int i = 0; i < 3; i++){
            for(int j = 0; j < 3; j++){
                if(board[i][j] != 'X' && board[i][j] != 'O'){
                    return false;
                }
            }
        }
        return true;
    }

    // Function for player to take turn
    void take_turn() {
        int position;
        std::cout << "Player " << current_player << " enter your move (0-8): ";
        std::cin >> position;
            for(int i = 0; i < move.size(); i++) {
                if(position == move[i]) {
                    std::cout << "Position already taken. Choose another position: ";
                    std::cin >> position;
                    i = -1; // Reset loop to check again
                }
            }
        move.push_back(position);
    }

    // Function to set position on board
    void set_position() {
        int pos = move.back();
        char symbol = (current_player == 1) ? 'X' : 'O';
        board[pos / 3][pos % 3] = symbol;
    }

    // Function to update board after each turn
    void update_board() {
        draw();
    }

    // Function to change player
    void change_player() {
        if(current_player == 1) {
            current_player = 2;
        } else {
            current_player = 1;
        }
    }

    // Function to end game
    void end_game() {
        if(is_winner()) {
            std::cout << "Player " << current_player << " wins!\n";
        } else if(filled_up()) {
            std::cout << "The game is a draw!\n";
        }
    }
            

A problem I realised I missed when initially writing my code was that I didn't make allowances for another player picking the same tile. So to fix this I included an if conditional to check if that position had already been chosen.

    for(int i = 0; i < move.size(); i++) {
        if(position == move[i]) {
            std::cout << "Position already taken. Choose another position: ";
            std::cin >> position;
            i = -1; // Reset loop to check again
        }
    }
            

Finally, it was time to put all the functions together in my main map. I including the function file so that it knew to reference those functions and starting putting everything together.

A benefit of putting the functions and declaring in seperate files means it makes the main app a lot easier to read.

    #include <iostream>
    #include <vector>
    #include "tttfunc.cpp"

    int main() {

    // Introduction to game
        introduction();

    // Game loop  
    while(!is_winner() && !filled_up()) {
        take_turn();
        set_position();
        update_board();
        if(!is_winner()) {
            change_player();
        } 
    }


    // End game message
    end_game();
    }            
            

Another issue that arose was that it was changing player and telling me the other player had won. To combat this, I added another if conditional that checked if there was a winner before changing player.

    if(!is_winner()) {
        change_player();
    }