Question

In C, build a connect 4 game with no graphical use interface. Build only the text interface. Use a 2D array as the Data structure. The skeleton of the game is provided for you, Build the game based on the guidelines below. The game does NOT need a mode where you play against the computer. It is simply a game of Connect 4 between player 1 and player 2.

SKELETON:

#include

// Initializing constants
#define NAME_LENGTH 30
#define BOARD_WIDTH 6
#define BOARD_HEIGHT 6
#define GAME 0
#define P_ONE 1
#define P_TWO 2
#define NO 0
#define YES 1

// Declaring variables
char p1[NAME_LENGTH];
char p2[NAME_LENGTH];
int bWidth = BOARD_WIDTH;
int bHeight = BOARD_HEIGHT;
int playCurrent = P_ONE; // Player 1 starts by default
int gameOver = GAME; // GAME = game is running, P_ONE = player one has won and so on
int p1Quit = NO;
int p2Quit = NO;

//print “Setting up the game”. Ask each player their name.

void Initialization() {
        printf("Setting up the game\n");
        printf("Enter your names\n");
        printf("Player 1:\n");
        scanf("%s", p1);
        printf("Player 2:\n");
        scanf("%s", p2);
}

void Teardown() {
        printf("Destroying the game\n");
}

/*accept a letter for which column of the game we are going to drop a disc into. Valid letters are A-G (7 columns). You should designate a letter for “Quit the game”. Input must be returned from this function*/

char AcceptInput() {
        char c;
        int valid = 0;
        do {
                printf("Player %d:\n", playCurrent);
                printf("Print a character to pick your column (A - G) or Q to quit\n");
                scanf(" %c", &c);
                if (c < 'A' || (c > 'G' && c != 'Q')) printf("Invalid character. Try again\n");
                else break;
                } while (1);
        return c;
}

/*pass the input data to this function. Since we do not have a “world” right now, choosing “A” is the “winning move”, all other letters make the game continue.*/

void UpdateWorld(char c) {
        if (c == 'Q') {
                if (playCurrent == P_ONE) {
                        p1Quit = YES;
                        gameOver = P_TWO;
                } else {
                        p2Quit = YES;
                        gameOver = P_ONE;
                }
        }
        if (c == 'A') {
                gameOver = playCurrent;
        }
        playCurrent = playCurrent == P_ONE ? P_TWO : P_ONE;
}

//Print the result calculated in the state of the world

void DisplayWorld() {
        if (p1Quit == YES) printf("Player 1 quit\n");
        if (p2Quit == YES) printf("Player 2 quit\n");
        if (gameOver == GAME) {
                printf("Game is currently in process\n");
        } else {
                printf("Player %d won\n", gameOver);
        }
}

/*call initialization, then loop until a flag is set (game over or a player quit), calling accept input, update and display. Outside of the loop, call teardown.*/

int main() {
        Initialization();
        while (gameOver == GAME && p1Quit == NO && p2Quit == NO) {
                char c;
                c = AcceptInput();
                UpdateWorld(c);
                DisplayWorld();
        }
        Teardown();
        return 0;
}

Connect Four is a game that alternates player 1 and player 2. You should keep track of whose turn it is next. Here are the guidelines for building the game.

1. We need to allocate the space for the game board. While this is a fixed size board, we will still dynamically allocate the space for the board in the initialization function.
2. Whenever we allocate memory, we need to make sure that we free it as well. Free the memory in the teardown function.
3. Print the game board in the display the world function. Use one character for an empty spot, one character for the discs for player one and another character for the discs for player two. You may use whatever characters you prefer. You may make the display as complex as you wish so long as we can clearly see what moves are available.
4. The remainder of the work to be done goes into “update the state of the world.”
   1. We must look through the column of the array and add the new disc into the array in the appropriate location based on the column that the player chose.
   2. We must signal to end the game if the column that the player chose is full.
   3. We must look for 4 discs belonging to one player in a straight line. The line can be horizontal, vertical, or diagonal. When we find this, we must signal end of the game.

Answer 1

Solution: below here is the C code for building this game

#include<stdio.h>
#include<string.h>
#include<string.h>
#include<math.h>
#include<windows.h>
#include<conio.h>
char check[4];
char yes[]="yes";
int  num_rows=12;
int num_cols=12;
int save_load();
int i=0,j=0,k,n,row,col,value,score_x=0,score_o=0,game_mode=0,number,Highscore,connecter=0,b=0,select_sides=0;
char board[100][100];
char read[10];
char name1[20];
char name2[20];
char save[]="save";
char sides[]="replace";
char red[]="redo";
char undo[]="undo";
char mains[]="start";
int position [100];
int redo[100];
void printboard();      //FUNCTIONS TO PRINT BOARD
void findposition();    //FUNCTION TO GET THE POSITION OF ELEMENT
void printnumber();     //FUNCTION TO PRINT NUMBER AND CHECK IT's VALIDTY
void scoreCheck();      //FUNCTION TO CHECK SCORE
void High_Score();      //FUNCTION TO DETERMINE THE HIGH SCORE
void select_side();     //FUNCTION TO SWAPE SELECT SIDES
void XML();             //FUNCTION TO READ FROM XML FILE
void instrctions();     //FUNCTIONS TO PRINT THE INSTRUCTIONS OF THE GAME
int main(){
    int flag=1;
    XML();              //FUNCTION TO READ FROM XML FILE
    findposition();     //FUNCTION TO GET THE POSITION OF ELEMENT
    start();            //FUNCTION FOR MAIN MENU
    score_o=0;score_x=0;b=0;                //NEW INTIALIZATION FOR NEW GAME
    while(flag==1){                         //FLAG TO START A NEW GAME
    printf("\nDo you want to go to main menue yes/no?");
    scanf("%s",&check);
    if(strcmp(check,yes)==0)start();        //ASKING FOR CONTINUE
    else flag=0;
    }
    return 0;
}
//FUNCTION TO STARTING THE MAIN MENU
void start(){
    XML();
    int choose;
    system("cls");                              //CLEAR SCREEN AFTER EACH PLAY
    for(i=0;i<15;i++)printf("\n");
    system("COLOR 1C");                         //CHANGING THE COLOR OF SCREEN
    printf("                              Welcome to connect four\n");              //WELCOME MESSAGE
    Sleep(1000);
    for(k=0;k<3;k++)printf("\n");
    system("COLOR EC");                           //CHANGING COLR OF THE SCREEN
    printf("                                   1-new game\n"                ////////////////////////////
           "                                   ----------  \n"              //                          //
          "                                   2-high scores\n"              //    MAIN MENU            //
          "                                   -------------\n"              ////////////////////////////
          "                                   3-load game\n"
          "                                   -----------\n"
          "                                   4-instruction\n"
          "                                   -------------      "
          "                                   \n");
    printf("choose from the previous options: \n");
    for(i=0;i<32;i++)printf("-");                                              //SCAN THE OPERATION TYPE FROM THE USER
    printf("\n");
    scanf("%d",&choose);                                                        //GET THE USER CHOOSE
    switch(choose){
        case 1: printnumber();break;
        case 2: High_Score();break;
        case 3: read[0]='l';save_load();printnumber();break;
        case 4: instrctions();break;
        default: printf("error please try again !!");
    }
}
void instrctions(){
    system("cls");                                       //PRINTING A NEW SCREEN
    system("COLOR 1C");
    printf("             **        HOW TO PLAY        ** \n\n\n");          //GAME INSTRUCTIONS
    printf("the aim of the game is to connect 4 (x) or 4 (0) vertically or\n horizontally or diagonally \n");
    printf("the player who connect 4 more than the other will be the winner\n\n\n");
    printf("press u or undo :    to go back one step , you can return back to first turn in the board\n");
    printf("press r or redo :    to go forward for one step, you can return the board again\n");
    printf("press s or save :    to save the game with its score \n");
    printf("to  load a game :    to load the game again you can use this option  \n                   just press start and choose load from menue\n");
    printf("press start     :    to go to main menue at any time\n");
    printf("press replace   :    to re-select sides this option can't be use in case of player v.s computer to prevent\n evil indeeds");
    char back[]="back";
    char main[6];
    printf("\n press back to return to main menue \n");         //GET BACK TO MAIN MENU TO CONTINUE PLAYING
    scanf("%s",&main);
    if(strcmp(main,back)==0){system("cls");start();}
}
//FUNCTION TO PRINT THE BOARD
void printboard(){
    int row,col,a,c;
    if(b==0){                               //INTIALIZATION TO BOARD WITH '.'
        for(a=0;a<num_rows;a++){
                for(c=0;c<num_cols;c++)
                board[a][c]='.';
        }
    }
    b++;
    system("cls");                          //TO CLEAR SCREEN AFTER EACH PLAY
    system("COLOR 4E");                     //TO COLOR THE BOARD
    for(row=0; row<num_rows; row++){        //PRINTING THE BOARD
        for(col=0; col<num_cols; col++){

            printf("| %c ",board[row][col]);
        }
        printf("|\n");
        for(a=0; a<num_cols; a++) printf("__");
        printf("\n");
    }
    for(a=0; a<num_cols; a++)printf("%*d",4,a+1);
    printf("\n");
}
//FUNCTION TO FIND THE POSITION OF ELEMENTS IN BOARD
void findposition(){
    for(i=0; i<num_cols; i++){
        position[i]=num_rows-1;
    }
}
//FUNCTION TO PRINT THE X & O AND CHECK THE BOARD
void printnumber(){

    if(read[0]!='l'){
    printf("choose the game mode \n");
    printf("--------------------\n");
    printf("                         1) Player V.s Player \n                         2) Player V.s Computer \n                         3)player V.s hard computer\n");
    scanf("%d",&game_mode);                 //GET THE GAME MODE FROM THE USER
    b=0;
    printboard();                           //FUNCTION TO PRINT BOARD
    findposition();                         //FUNCTION TO GET THE POSITION OF ELEMENT
    }
    printf("please enter player (1) name: ");       //GETTING THE PLAYERS NAME FROM THE USER
    scanf("%s",&name1);
        if(game_mode==1){
    printf("please enter player (2) name: ");
        scanf("%s",&name2);
        }

    for(i=connecter; i<num_cols*num_rows+select_sides; i++){

        if(i%2==0){                         //SWAPING TURNS
            printf(" %s's turn\n choose the column to put x in: ",name1);       //PRINTING PLAYER'S TURNS
            scanf("%s",&read);
            number=atoi(read);

        }else{
            if (game_mode==1) player2();                    //CALLING THE FUNCTIONS OF PLAYERS MODE
            else if(game_mode==2)computer();
            else medium_computer();
        }
        if(strcmp(read,sides)==0){select_side();i--;}
        else if(strcmp(read,mains)==0){
                XML();
                printf("WARNING the game won't be save\n do you want to save yes/no ? ");           //WARNING IN CASE OF NOT SAVING FILE
                scanf("%s",check);
                if(strcmp(check,yes)==0){

                    read[0]='s';
                    save_load();
                }
                score_x=0;score_o=0;findposition();b=0;printboard();
                start();
                break;
        }
       else if(strcmp(read,save)==0||(read[0]=='s'&&read[1]=='\0')){     //COMPARISON IF THE USER WANT TO SAVE OR LOAD

            save_load();
            i--;
        }else if((read[0]=='r'&&read[1]=='\0')||strcmp(read,red)==0||(read[0]=='u'&&read[1]=='\0')||strcmp(read,undo)==0){    //CHECK FOR UNDO AND REDO
            redo_undo();
        }else if(number<1||number>num_cols||board[0][number-1]!='.'){                   //BOARD LIMITS
            printf("out of scoop please try again\n");
            i--;
        }else{                                                 //PRINTING X AND O
            redo[i]=number-1;
            value=position[number-1];
            if(i%2==0)board[value][number-1]= 'X';
            else board[value][number-1]= 'O';
            position[number-1] -=1;
            scoreCheck ();                                  //CHECK SCORE
            printboard();                                   //PRINTING THE BOARD
            if(i%2==0) system("COLOR 5E");                  //CHANGING THE COLOR OF SCREEN FOR EACH PLAYER
            else system("COLOR BC");
            printf("Score X =  %d    Score O =%d\n ",score_x,score_o);          //PRINTING THE SCORE
             printf("             **        HOW TO PLAY        ** \n\n\n");          //GAME INSTRUCTIONS
            printf("the aim of the game is to connect 4 (x) or 4 (0) vertically or\n horizontally or diagonally \n");
            printf("the player who connect 4 more than the other will be the winner\n\n\n");
            printf("press u or undo :    to go back one step , you can return back to first turn in the board\n");
            printf("press r or redo :    to go forward for one step, you can return the board again\n");
            printf("press s or save :    to save the game with its score \n");
            printf("to  load a game :    to load the game again you can use this option  \n                   just press start and choose load from menue\n");
            printf("press start     :    to go to main menue at any time\n");
            printf("press replace   :    to re-select sides this option can't be use in case of player v.s computer to prevent\n evil indeeds\n");
        }
    }
    if(i==num_rows*num_cols) {

            High_Score();                    //CALLING HIGH SCORE FUNCTION WHEN GAME IS ENDED
            printf("\nDo you want to save ? (yes/no ) \n");
            scanf("%s",&check);
            if(strcmp(check,yes)==0){
                read[0]='s';
                save_load();
            }
    }
}
//FUNCTION TO CHECK CONNECT FOUR OR NOT
char  checkFour(int a_1,int a_2,int b_1,int b_2,int c_1,int c_2,int d_1,int d_2){
    if (board[a_1][a_2]==board[b_1][b_2]&&board[b_1][b_2]==board[c_1][c_2]&&board[c_1][c_2]==board[d_1][d_2]&&board[a_1][a_2]!='.')
        return board[a_1][a_2];
    return 'a';
}
//FUNCTION TO CHECK SCORE AFTER EACH PLAY
void scoreCheck (){
    int i=1,j=1,counter =0,a,c=1,b=-1;
    for(a=0; a<4; a++){
        i=-i;
        j=j*pow(-1,counter); //LOOPING TO CHCK SCORE IN FOUR DIRECTIONS
        counter++;
        if(num_rows>value+i*3&&value+i*3>=0&&num_cols>number-1+j*3&&number-1+j*3>=0){
            if('X'==checkFour(value,number-1,value+i,number-1+j,value+i*2,number-1+j*2,value+i*3,number-1+j*3)) score_x+=1;
            if('O'==checkFour(value,number-1,value+i,number-1+j,value+i*2,number-1+j*2,value+i*3,number-1+j*3)) score_o+=1;
        }
        if ('X'==checkFour(value,number-1,value+j,number-1+i,value-j,number-1-i,value-2*j,number-1-2*i)) score_x+=1;
        if ('O'==checkFour(value,number-1,value+j,number-1+i,value-j,number-1-i,value-2*j,number-1-2*i)) score_o+=1;
    }
    for(a=0; a<2; a++){
        c=-c;
        b*=-1;
        if(num_rows>value+3*c&&value+3*c>=0){
            if('X'==checkFour(value,number-1,value+c,number-1,value+2*c,number-1,value+3*c,number-1))score_x+=1;
            if('O'==checkFour(value,number-1,value+c,number-1,value+2*c,number-1,value+3*c,number-1))score_o+=1;
        }
        if(num_cols>number-1+3*c&&number-1+3*c>=0){
            if('X'==checkFour(value,number-1,value,number-1+c,value,number-1+2*c,value,number-1+3*c))score_x+=1;
            if('O'==checkFour(value,number-1,value,number-1+c,value,number-1+2*c,value,number-1+3*c))score_o+=1;
        }
        if('X'==checkFour(value,number-1,value,number-1+b,value,number-1-b,value,number-1-2*b)&&value-2*b>=0)score_x+=1;
        if('O'==checkFour(value,number-1,value,number-1+b,value,number-1-b,value,number-1-2*b)&&value-2*b>=0)score_o+=1;
    }
}
//FUNCTION FOR UNDO AND REDO
void redo_undo(){
    int old_scorex=score_x;
    int old_scoreo=score_o;
    if(strcmp(read,undo)==0||(read[0]=='u'&&read[1]=='\0')){             //CALLING THE FUNCTION WHEN UUSER ENTER U OR UNDO
        i--;
        if(i<0) {}                                                       //IF I<0 HE CAN'T UNDO ANY STEP SO THIS FUNCTION IS USELESS
        else{
            int col = redo[i];
            number=col+1;
            value=position[number-1]+1;
            scoreCheck();                               //CHECKING THE SCORE
            if(score_x>old_scorex)score_x=score_x-2*(score_x-old_scorex);               //CECK THE NEW SCORE AFTER REDO
            if(score_o>old_scoreo)score_o=score_o-2*(score_o-old_scoreo);
            position[col]+=1;
            number=col+1;
            row=position[col];
            board[row][col]='.';
            i--;
            j++;
        }
    }
    else{
        if(j<1){
            i--;
        }else{
            int col=redo[i];
            row=position[col];
            if(i%2==0)board[row][col]='X';              //IT RETURNS THE X REMOVED BY UNDO FUNCTION
            else board[row][col]='O';
            position[col]-=1;
            value=row;number=col+1;
            scoreCheck();
            j--;
        }
    }
    printboard();                                               //CHEXK SCORE AFTER UNDO & REDO
    printf("Score X = %d    Score O =%d \n",score_x,score_o);   //PRINTING THE SCORE
}
//FUNCTION TO PLAY PLAYER VS PLAYER
int player2 (){

    printf("%s's turn\n choose the column to put 0 in: ",name2);          //PRINTING TURN TO PLAYER TWO
    scanf(" %s",read);                                          //SCAN THE NUMBR FROM PLAYER TWO
    number=atoi(read);
    return number;
}
//FUNCTION TO PLAY VS COMPUTER EASY
int computer (){
    printf("Computer  turn: ");
    if ((read[0] == 'u'&&read[1]=='\0')||strcmp(read,undo)==0) return;           //FOR UNDO AND REDO RETURN NOTHING TO GET BACK FOR PLAYER TURN
    else{
        number=1+(rand()%num_cols);                     //COMPUTER PLAYING IN A RANDOM WAY
        return number;
    }
}
//FUNCTION FOR SAVE AND LOAD BINRY !!!!!!!!
int save_load(){

    int k=num_rows-1 ,n,load;       //INTIALIZATION AND DECLERATION VARAIABLES
    static int counter=6;
    char byte = 0;
    FILE*save;
    if((read[0]=='s'&&read[1]=='\0')||strcmp(read,save)==0){


            char fileName[100],str[100] ;
        puts("enter the file name : ");                     //GET THE FILE NAME FROM THE USER
        scanf("%s",fileName);
        sprintf(str,"%s%s",fileName,".shehab");             //ADD THE EXE TO THE FILE NAME
        FILE*save=fopen(str,"wb");                          //OPEN THE FILE FOR WRITE BINRY
         byte |= num_cols<<4;
            byte |= num_rows;
            fprintf(save,"%c",byte);
            byte=0;

        for(n=0;n<num_cols;n++){
            k=num_rows-1;
            while(k>=0){                                    //WRITING IN BINRY FILE
                if(board[k][n]=='X')load=3;
                else if(board[k][n]=='O')load=2;
                else if(board[k][n]=='.')load=0;
                byte |= load<<counter;                      //SHIFTING THE BITS
                counter-=2;
                if(counter==-2){
                    counter=6;
                    fprintf(save,"%c",byte);
                    byte = 0;
                }if(load==0)break;
                k--;
            }
        }
        if(counter!=-2)fprintf(save,"%c",byte);
        fclose(save);
        printf("Do you want to continue yes/no ? \n");
        scanf(" %s",&check);
        if(strcmp(yes,check)==0){}
        else exit(main);
    }
   else if(read[0]=='l'){     //LOADING THE BINRY FILE

        i=0;
        char fileName[100],str[100] ;               //DECLARTION
        puts("enter the file name : ");             //GET THE FILE NAME FROM THE USER
        scanf("%s",fileName);
        strcat(fileName, ".shehab");                 //ADD THE EXETO THE FILE NAME
        sscanf(str,"%s",fileName);
        printf(" 1) Player V.s Player \n 2) Player V.s Computer \n 3) medium computer \n");
        scanf("%d",&game_mode);                        //ASK THE USER FOR GAME LOADING MODE
        save=fopen(fileName,"rb");                     //READ BINRY FROM THE FILE
        fscanf(save,"%c",&byte);

        num_rows= byte &0xF;
        num_cols= (byte>>4)&0xF;

        b=0;findposition();printboard();system("cls");
        counter = 6;
        for(n=0;n<num_cols;n++){
            k=num_rows-1;
            while(k>=0){                            //SHIFTING AND READING FROM BINRY FILE
                if (counter == 6) {
                    fscanf(save,"%c",&byte);
                }
                load = (byte>>counter) & 3;
                if (load == 0) {
                } else if (load == 2) {
                    i++;connecter++;
                    board[k][n]='O';
                    value=k;number=n+1;
                    position[number-1]--;
                    scoreCheck();                            //CHECK THE SCORE AFTER READING
                } else if (load == 3) {
                    i++;connecter++;
                    board[k][n]='X';
                    value=k;number=n+1;
                    position[number-1]--;
                    scoreCheck();
                }
                counter-=2;
                if(counter==-2){
                    counter=6;
                }
                k--;
            if (load==0)break;
        }

    }fclose(save);                      //closing the file
    printboard();
    printf("Score X = %d    Score O =%d \n",score_x,score_o);       //PRINTING THE SCORE
    }
}
//AI FUNCTION FOR PLAYING VS COMPUTER
int medium_computer(){
    // THE FIRST PART OF AI THE MAIN IDEA OF THE AI IS WHEN THE TURN IS TO COMPUTER THE COMPUTER PUT X IN THE BOARD AND IF THE SCORE OF X INC. THEN
    // IT'S THE BEST PLACE FOR O TO PREVENT X FROM CONNECTING FOUR
    //IF THERE IS NO DANGER FROM X TO WIN SO THE COMPUTER STARTS TO THINK ABOUT THE BEST WAY TO PLAY SO IT'S SCORE INC.
    int old_scorex=score_x;
    int old_scoreo=score_o;
    //CONNECT_4X REFERS TO ANY  FOUR X
    //CONNECT3_X REFERES TO EVERY THREE X AFTER EACH OTHER
    //CONNECT4_0 REFERES TO EVERY FOUR O AFTER EACH OTHER
    //CONNECT3_0 REFERES TO EVERY THREE O AFTER EACH OTHER
    //CONNECT2_0 REFERES TO EVERY TWO O AFTER EACH OTHER
    //CONNECT1_0 REFERES TO EVERY ONE O AND HAVE 3 SPACES AFTER IT OR BEFORE IT
    int connect4_x=-1,connect3_x=-1 , connect4_o=-1,connect3_o=-1,connect2_o=-1,connect1_o=-1;
    int num=number,critical;
    number=number-4;
    //HERE THE COMPUTER START TO DETECT THE BEST WAY FOR O TO PREVENT X FROM WINNIG
    for(k=-3; k<=3; k++){
        number++;
        if(number<1||position[number-1]==-1||number>num_cols){
            continue;
        }else{
            value=position[number-1];
            board[value][number-1]= 'X';
            scoreCheck();
            board[value][number-1]= '.';
            if(score_x-old_scorex>0){
                connect4_x=number;
                score_x=old_scorex;
            }
            score_x=old_scorex;
            if(score_x-old_scorex>0)break;
        }
    }
    //AFTER COMPUTER FAIL IN FINDING THE PLACE WHERE IF X PLAYS ON IT WILL WIN HE BEGIN TO CHECK ONE CASE IF THERE IS 2 X ON THE
    //SAME ROW AND HAS TWO OR MORE SPACE BEFORE AND AFTER IT HE CONSIDER THIS CASE AS A CRITICAL ONE AND PREDICT WITH 2 STEPS
    if(connect4_x==-1){
        number=num;
        value=position[number-1];
        if(board[value+1][number-2]=='X' && ((value+1==position[number]&&value+1==position[number+1]&&value+1==position[number-3])||(value+1==position[number]&&value+1==position[number-3]&&value+1==position[number-4])))
            connect3_x=number+1;

        else if((board[value+1][number]=='X')&& ((value+1==position[number+1]&&value+1==position[number+2]&&value+1==position[number-2])||(value+1==position[number-2]&&value+1==position[number-3]&&value+1==position[number+1])))
            connect3_x=number-1;

    }
    //AFTER HE FAILS TO DEFENCE HE TRIES TO ATTACK
    //HE WILL CHECK THE BEST WAY TO PLAY O TO WIN
    if(connect3_x==-1&&connect4_x==-1){
        for(n=0; n<num_cols; n++){
            number=n+1;
            if(position[n]>=0){
                value=position[n];
                board[value][n]='O';
                number=n+1;
                scoreCheck();
                if(score_o-old_scoreo>0){
                    connect4_o=number;
                    score_o=old_scoreo;
                    score_x=old_scorex;
                }
                 score_o=old_scoreo;
                 score_x=old_scorex;
            }
            if(n<num_cols-1&&connect4_o==-1&&position[n+1]>=0){
                value=position[n+1];
                board[value][n+1]='O';
                number=n+2;
                scoreCheck();
                if (score_o-old_scoreo>0){
                    connect3_o=number;
                    score_o=old_scoreo;
                    score_x=old_scorex;
                }
                 score_o=old_scoreo;
                 score_x=old_scorex;
            }
            if(n<num_cols-2&&connect3_o==-1&&position[n+2]>=0&&connect4_o==-1){
                value=position[n+2];
                board[value][n+2]='O';
                number=n+3;
                scoreCheck();
                if (score_o-old_scoreo>0){
                    connect2_o=number;
                    score_o=old_scoreo;
                    score_x=old_scorex;
                }
                 score_o=old_scoreo;
                 score_x=old_scorex;
            }
            if(n<num_cols-3&&connect2_o==-1&&position[n+3]>=0&&connect3_o==-1&&connect4_o==-1){
                value=position[n+3];
                board[value][n+3]='O';
               number=n+4;
                scoreCheck();
                if(score_o-old_scoreo>0){
                    connect1_o=number;
                    score_o=old_scoreo;
                    score_x=old_scorex;
                }
                 score_o=old_scoreo;
                 score_x=old_scorex;
            }
            if(position[n]>=0){
                value=position[n];
                board[value][n]='.';
            }
            if(n<num_cols-1&&position[n+1]>=0){
                value=position[n+1];
                board[value][n+1]='.';
            }
            if(n<num_cols-2&&position[n+2]>=0){
                value=position[n+2];
                board[value][n+2]='.';
            }
            if(n<num_cols-3&&position[n+3]>=0){
                value=position[n+3];
                board[value][n+3]='.';
            }
        }
    }
    number=num;
    if ((read[0]=='u'&&read[1]=='\0')||strcmp(read,undo)==0||strcmp(read,sides)==0){

        return ;
    }else if(connect4_x>-1){
        number=connect4_x;
        return number;
    }else if(connect3_x>-1){
        number=connect3_x;
        return number;
    }else if(connect4_o>-1){
        number=connect4_o;
        return number;
    }else if(connect3_o>-1){
        number=connect3_o;
        return number;
    }else if(connect2_o>-1){
        number=connect2_o;
        return number;
    }else if(connect1_o>-1){
        number=connect1_o;
        return number;
    }else {
            for(n=0;n<num_cols;n++){
                    value=position[n];
                if (board[value][n]=='.'){
                number=n+1;
                return number;
                }
            }
    }
}
//FUNCTION TO READ FROM XML FILE
void XML (){
    //START REFEERE TO START OF INDEX TO CONFIGURATION TAG
    //END REFEERE TO END OF INDEX OF CONFIGURATION TAGG
    //START _W REFEERE TO STARTING INDEX OF WIDTH TAG
    //END_W REFEERE TO ENDING INDEX OF WIDTH TAG
    //START _H REFFERE TO START INDEX OF HEIGHT TAG
    //END_H REFFERE TO END INDEX OF HIEGHT TAG
    //START HS REFFERE TO START INDEX OF HIGHSCORES TAG
    //END_HS REFFERE TO END INDEX OF HIGHSCORE TAG
    //LEN REFFERE TO THE LENGTH BETWEEN TWO CONFIGURTIONS
    //a IN A COUNTER
    // HS ------> HIGHSSCORE    H -------> HEIGHT      W ---------> WIDTH
    char y,x[200]= {'0'},conf_1[]="<Configurations>",width_1[]="<Width>",height_1[]="<Height>",highscores_1[]="<Highscores>";
    char conf_2[]="</Configurations>",width_2[]="</Width>",height_2[]="</Height>",highscores_2[]="</Highscores>";
    int i=0,start,end,start_w,end_w,start_h,end_h,start_hs,end_hs,len,a,size,HS,H,W;
    FILE *file= fopen("project.xml", "r");              //READING FROM THE FILE
    while((y=fgetc(file))!=EOF){
        if(y!=' '&&y!='\n'&&y!='\t'){           //IGNORING ANY SPACES OR TABS OR BREAKING LINE
            x[i]=y;
            i++;
            len++;
        }
    }
    start=over_lapping(conf_1,x);               //CALLING OVERLAPPING FUNCTION
    end =over_lapping(conf_2,x);
    size=end-start+1;
    char array[size];                           //ARRAY TO RED BETWEEN TWO CONFIGRATIONS TAGS
    for(a=0; a<size; a++)array[a]=x[start+a];   // INTIALIZATION FOR NWE ARRAY
    start_w=over_lapping(width_1,array);
    end_w=over_lapping(width_2,array);
    char row [3];                               //CHECKING OPENING AND CLOSING THE TAGS IN RIGHT WAY
    row[0]=array[start_w+7];
    row[1]=array[start_w+8];
    row[2]='\0';
    if(start_w!=-1&&end_w!=-1&&(end_w-start_w==8||end_w-start_w==9)&&atoi(row)>=4) W=atoi(row);

    else{                                       //SET THE DEFULT IN THERE IS WRONG IN READING THE XML FILE
        system("COLOR 8C");
        W=7;
        printf("Width is Not found !! the defult is Width =7\n");
        printf("Wait to load the default!!\n");
        Sleep(5000);
    }
    start_h=over_lapping(height_1,array);       //CALLING THE OVERLAPPING FUNCTION
    end_h=over_lapping(height_2,array);
    char col [3];                                  //CHECK OPENING AND CLOSING THE TAGS IN WRIGHT WAY
    col[0]=array[start_h+8];
    col[1]=array[start_h+9];
    col[2]='\0';
    if(start_h!=-1&&end_h!=-1&&(end_h-start_h==9||end_h-start_h==10)&&atoi(col)>=4)H=atoi(col);
    else{
        H=6;                                        //SET THE DEFULT IF THERE IS ERROR WHILE READING FROM XML FILE
        printf("Height is Not found !! the defult is Height =6\n");
        printf("Wait to load the default!!\n");
        Sleep(5000);
    }
    start_hs=over_lapping(highscores_1,array);
    end_hs=over_lapping(highscores_2,array);        //CALLING OVER LAPPING FUNCTIONS
    char score[3];
    score[0]=array[start_hs+12];                    //PUTTING BETWEEN TAGS IN ARRAY FOR READING WITH ATOI
    score[1]=array[start_hs+13];
    score[2]='\0';
    if(start_hs!=-1&&end_hs!=-1&&end_hs-start_hs==13||end_hs-start_hs==14)HS=atoi(score);
    else{
        HS=5;                                       //SET THE DEFULT VALUE
        printf("High_score is Not found !! the defult is Highscore =5\n");      //PRINTING ERROR
        printf("Wait to load the default!!\n");                                 //ERROR MESSAGE
        Sleep(5000);
    }
    num_cols=W;                                     //CHANGING THE GLOBAL VALUE FOR WIDTH
    num_rows=H;                                     //CHANGING THE GLOBAL VALUE FOR HEIGHT
    Highscore=HS;                                   //CHANGING THE GLOBAL VAUE FOR HIGH SCORE
}
//FUNCTION TO CHECK IF WORD IS FOUND IN STRING OR NOT
int over_lapping(char s1[],char s2[]){
    int counter=-1,i=0;
    while(s2[i]!='\0'){
        int j=0;
        if(s2[i]==s1[j]){
            int k=i;
            while(s2[k]==s1[j] && s1[j]!='\0'){
                k++;
                j++;
            }
            if(s1[j]=='\0'){
                counter=i;
            }
        }
        i++;
    }
    return counter;
}
//FUNCTION TO PRINT THE HIGH SCORE LIST
void High_Score(){
    int scores[100]= {0},i,counter=-1,j=0,temp=0;
    FILE *file= fopen("High_scores.text", "r");         //READING FROM THE FILE
    for(i=0; i<20; i++){
        fscanf(file,"%d",&scores[i]);
        if(scores[i]!=0) counter++;
    }
    if(score_x>score_o) scores[counter+1]=score_x;
    else  scores[counter+1]=score_o;
    for(i=0; i<Highscore; i++){             //SORTING THE ARRAY FOR PRINTING
        for(j=0; j<Highscore; j++)
            if(scores[j]<scores[i]){
                temp=scores[i];
                scores[i]=scores[j];
                scores[j]=temp;
            }
    }
    printf("HIGH SCORE LIST IS : ");                    //PRINING THE HIGH SCORE LIST
    file= fopen("High_scores.text", "w");               // WRITING THE HIGH SCORE LIST IN FILE
    for(i=0; i<Highscore; i++){
        printf("%d   ",scores[i]);
        fprintf(file,"%d  ",scores[i]);
    }
    fclose(file);
}
//FUNCTIONS TO SWAPE SELECT SIDES OF TWO PLAYERS
void select_side(){
    if(game_mode==1){
        printf("Enter the new name for %s :",name1);        //GETTING THE USER NAME
        scanf("%s",&name1);
        printf("Enter the new name for %s :",name2);
        scanf("%s",&name2);
        select_sides=1;
    }
}

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