c-connect-four/main.c

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <unistd.h>
#include <assert.h>

/* Game Specific defines */
#define ROWS 7
#define COLUMNS 6
#define TIME 0.6
#define PLAYER1 '0'
#define PLAYER2 'X'

/* Printf colour defines */
#define BOLDYELLOW  "\033[1m\033[33m"      /* Bold Yellow */
#define BOLDRED     "\033[1m\033[31m"      /* Bold Red */
#define BOLDWHITE   "\033[1m\033[37m"      /* Bold White */
#define RESET       "\033[0m"

/* Global board, saves passing 2D array pointers */
char board[ROWS][COLUMNS];

void print_board();
void clear_board();

void player_choice(char player);
void ai_choice(char player);

char check_win();
int check_free_space();

char flag = ' ';

int main(int argc, char *argv[]){
    clear_board();
    while(check_free_space() != 0 && flag == ' '){
        print_board();
        player_choice(PLAYER1);
        flag = check_win();

        print_board();
        player_choice(PLAYER2);
        flag = check_win();
    }

    printf(BOLDWHITE "%c won!" RESET, flag);

	return 0;
}


void print_board(){
    int r, c;
    c = 0;
    system("clear");
    //printf("\nFree Spaces: %d\n", check_free_space());

    printf(BOLDWHITE "  1    2    3    4    5    6    \n" RESET);

    for(r = 0; r < ROWS; ++r){
        for(c = 0; c < COLUMNS; ++c){
            //PLAYER 1 COLOURS
            if(board[r][c] == PLAYER1){
                printf("[ ");
                printf(BOLDRED "%c" RESET ,board[r][c]);
                printf(" ]");
            }
            //PLAYER 2 COLOURS
            else if(board[r][c] == PLAYER2){
                printf("[ ");
                printf(BOLDYELLOW "%c" RESET ,board[r][c]);
                printf(" ]");
            }
            else{
                printf("[ %c ]", board[r][c]);
            }
        }
        printf("\n");
    }
}


void clear_board(){
    int r, c;
    for(r = 0; r < ROWS; ++r){
        for(c = 0; c < COLUMNS; ++c){
            board[r][c] = ' ';
        } 
    }
}

void player_choice(char player){
    unsigned int frametime = 30000;
    int chosenCol;

    printf(BOLDWHITE "\n[%c] Enter column (1-6)\n> " RESET, player);
    scanf("%d", &chosenCol);

    if(chosenCol > 6){
       printf(BOLDRED "\n[%c] Cannot play here, skipping...\n" RESET, player);
       sleep(1);
    } else {
        chosenCol--; //arrays start with 0
        for(int r = 0; board[r][chosenCol] == ' '; ++r){

            // Check if the next tile is not empty (occupied)
            if(board[r+1][chosenCol] != ' '){
                board[r][chosenCol] = player;
                break;
            }
            //check if we've hit the last row
            if(r >= COLUMNS){
                board[r][chosenCol] = player;
                break;
            }

            // Animation for dropping the piece down
            board[r][chosenCol] = player;
            print_board();
            usleep(frametime);
            board[r][chosenCol] = ' ';
            print_board();
            usleep(frametime);
        }
    }
}

void ai_choice(char player){
    //TODO: Implement ""AI""
}

char check_win(){
    char flag = ' ';

    //no i know there is a better way to check for a win cond.
    //buuttt ill do what i wanna
    //and repeat all the checks twice (player 1 and player 2)!

    //check vert
    for(int i = 0; i < COLUMNS; ++i) {
        for(int j = 0; j < ROWS; ++j) {
            if(board[i][j] == PLAYER1 && board[i][j+1] == PLAYER1 && board[i][j+2] == PLAYER1 && board[i][j+3] == PLAYER1){
                flag = PLAYER1;
           }
       } 
    }

    //check horiz
    for(int i = 0; i < ROWS; ++i) {
        for(int j = 0; j < COLUMNS; ++j) {
            if(board[i][j] == PLAYER1 && board[i+1][j] == PLAYER1 && board[i+2][j] == PLAYER1 && board[i+3][j] == PLAYER1){
                flag = PLAYER1;
           }
       } 
    }

    //check diagright
    for(int i = 0; i < ROWS; ++i){
        for(int j = 0; j < COLUMNS; ++j) {
            if(board[i][j] == PLAYER1 && board[i-1][j+1] == PLAYER1 && board[i-2][j+2] == PLAYER1 && board[i-3][j+3] == PLAYER1){
                flag = PLAYER1;
            }
        }
    }
    //check diagleft
    for(int i = 0; i < ROWS; ++i){
        for(int j = 0; j < COLUMNS; ++j) {
            if(board[i][j] == PLAYER1 && board[i-1][j-1] == PLAYER1 && board[i-2][j-2] == PLAYER1 && board[i-3][j-3] == PLAYER1){
                flag = PLAYER1;
            }
        }
    }

    //check vert
    for(int i = 0; i < COLUMNS; ++i) {
        for(int j = 0; j < ROWS; ++j) {
            if(board[i][j] == PLAYER2 && board[i][j+1] == PLAYER2 && board[i][j+2] == PLAYER2 && board[i][j+3] == PLAYER2){
                flag = PLAYER2;
           }
       } 
    }

    //check horiz
    for(int i = 0; i < ROWS; ++i) {
        for(int j = 0; j < COLUMNS; ++j) {
            if(board[i][j] == PLAYER2 && board[i+1][j] == PLAYER2 && board[i+2][j] == PLAYER2 && board[i+3][j] == PLAYER2){
                flag = PLAYER2;
           }
       } 
    }

    //check diagright
    for(int i = 0; i < ROWS; ++i){
        for(int j = 0; j < COLUMNS; ++j) {
            if(board[i][j] == PLAYER2 && board[i-1][j+1] == PLAYER2 && board[i-2][j+2] == PLAYER2 && board[i-3][j+3] == PLAYER2){
                flag = PLAYER2;
            }
        }
    }
    //check diagleft
    for(int i = 0; i < ROWS; ++i){
        for(int j = 0; j < COLUMNS; ++j) {
            if(board[i][j] == PLAYER2 && board[i-1][j-1] == PLAYER2 && board[i-2][j-2] == PLAYER2 && board[i-3][j-3] == PLAYER2){
                flag = PLAYER2;
            }
        }
    }

    return flag; 

}

int check_free_space(){
    int r, c;
    int sp = 0;

    for(r = 0; r < ROWS; ++r){
        for(c = 0; c < COLUMNS; ++c){
            if(board[r][c] == ' ') 
                ++sp;
        } 
    }

    return sp;
}