Create Tic_Tac_Toe-game.cpp

Tic_Tac_Toe-game.cpp

@@ -0,0 +1,253 @@
+//Tic Tac Toe
+#include<bits/stdc++.h>
+using namespace std;
+#define COMPUTER 1
+#define HUMAN 2
+#define SIDE 3
+#define COMPUTERMOVE 'O'
+#define HUMANMOVE 'X'
+void showBoard(char board[][SIDE])
+{
+printf("\t\t\t %c | %c | %c \n", board[0][0], board[0][1], board[0][2]);
+printf("\t\t\t-----------\n");
+printf("\t\t\t %c | %c | %c \n", board[1][0], board[1][1], board[1][2]);
+printf("\t\t\t-----------\n");
+printf("\t\t\t %c | %c | %c \n\n", board[2][0], board[2][1], board[2][2]);
+}
+void showInstructions()
+{
+printf("\nChoose a cell numbered from 1 to 9 as below and play\n\n");
+printf("\t\t\t 1 | 2 | 3 \n");
+printf("\t\t\t-----------\n");
+printf("\t\t\t 4 | 5 | 6 \n");
+printf("\t\t\t-----------\n");
+printf("\t\t\t 7 | 8 | 9 \n\n");
+}
+void initialise(char board[][SIDE])
+{
+// Initially the board to '*' as said
+for (int i=0; i<SIDE; i++)
+{
+for (int j=0; j<SIDE; j++)
+board[i][j] = '*';
+}
+}
+void declareWinner(int whoseTurn)
+{
+if (whoseTurn == COMPUTER)
+printf("COMPUTER has won\n");
+else
+printf("HUMAN has won\n");
+}
+bool rowCrossed(char board[][SIDE])
+{
+for (int i=0; i<SIDE; i++)
+{
+if (board[i][0] == board[i][1] &&
+board[i][1] == board[i][2] &&
+board[i][0] != '*')
+return (true);
+}
+return(false);
+}
+bool columnCrossed(char board[][SIDE])
+{
+for (int i=0; i<SIDE; i++)
+{
+if (board[0][i] == board[1][i] &&
+board[1][i] == board[2][i] &&
+board[0][i] != '*')
+return (true);
+}
+return(false);
+}
+bool diagonalCrossed(char board[][SIDE])
+{
+if (board[0][0] == board[1][1] &&
+board[1][1] == board[2][2] &&
+board[0][0] != '*')
+return(true);
+if (board[0][2] == board[1][1] &&
+board[1][1] == board[2][0] &&
+board[0][2] != '*')
+return(true);
+return(false);
+}
+bool gameOver(char board[][SIDE])
+{
+return(rowCrossed(board) || columnCrossed(board) || diagonalCrossed(board) );
+}
+int minimax(char board[][SIDE], int depth, bool isAI)
+{
+int score = 0;
+int bestScore = 0;
+if (gameOver(board) == true)
+{
+if (isAI == true)
+return -10;
+if (isAI == false)
+return +10;
+}
+else
+{
+if(depth < 9)
+{
+if(isAI == true)
+{
+bestScore = -999;
+for(int i=0; i<SIDE; i++)
+{
+for(int j=0; j<SIDE; j++)
+{
+if (board[i][j] == '*')
+{
+board[i][j] = COMPUTERMOVE;
+score = minimax(board, depth + 1, false);
+board[i][j] = '*';
+if(score > bestScore)
+{
+bestScore = score;
+}
+}
+}
+}
+return bestScore;
+}
+else
+{
+bestScore = 999;
+for (int i = 0; i < SIDE; i++)
+{
+for (int j = 0; j < SIDE; j++)
+{
+if (board[i][j] == '*')
+{
+board[i][j] = HUMANMOVE;
+score = minimax(board, depth + 1, true);
+board[i][j] = '*';
+if (score < bestScore)
+{
+bestScore = score;
+}
+}
+}
+}
+return bestScore;
+}
+}
+else
+{
+return 0;
+}
+}
+}
+int bestMove(char board[][SIDE], int moveIndex)
+{
+int x = -1, y = -1;
+int score = 0, bestScore = -999;
+for (int i = 0; i < SIDE; i++)
+{
+for (int j = 0; j < SIDE; j++)
+{
+if (board[i][j] == '*')
+{
+board[i][j] = COMPUTERMOVE;
+score = minimax(board, moveIndex+1, false);
+board[i][j] = '*';
+if(score > bestScore)
+{
+bestScore = score;
+x = i;
+y = j;
+}
+}
+}
+}
+return x*3+y;
+}
+// A function to play Tic-Tac-Toe
+void playTicTacToe(int whoseTurn)
+{
+char board[SIDE][SIDE];
+int moveIndex = 0, x = 0, y = 0;
+initialise(board);
+showInstructions();
+while (gameOver(board) == false && moveIndex != SIDE*SIDE)
+{
+int n;
+if (whoseTurn == COMPUTER)
+{
+n = bestMove(board, moveIndex);
+x = n / SIDE;
+y = n % SIDE;
+board[x][y] = COMPUTERMOVE;
+printf("COMPUTER has put a %c in cell %d\n\n", COMPUTERMOVE,
+n+1);
+showBoard(board);
+moveIndex ++;
+whoseTurn = HUMAN;
+}
+else if (whoseTurn == HUMAN)
+{
+printf("You can insert in the following positions : ");
+for(int i=0; i<SIDE; i++)
+for (int j = 0; j < SIDE; j++)
+if (board[i][j] == '*')
+printf("%d ", (i * 3 + j) + 1);
+printf("\n\nEnter the position = ");
+scanf("%d",&n);
+n--;
+x = n / SIDE;
+y = n % SIDE;
+if(board[x][y] == '*' && n<9 && n>=0)
+{
+board[x][y] = HUMANMOVE;
+printf ("\nHUMAN has put a %c in cell %d\n\n", HUMANMOVE,
+n+1);
+showBoard(board);
+moveIndex ++;
+whoseTurn = COMPUTER;
+}
+else if(board[x][y] != '*' && n<9 && n>=0)
+{
+printf("\nPosition is occupied, select any one place from the
+available places\n\n");
+}
+else if(n<0 || n>8)
+{
+printf("Invalid position\n");
+}
+}
+}
+if (gameOver(board) == false && moveIndex == SIDE * SIDE)
+printf("It's a draw\n");
+else
+{
+if (whoseTurn == COMPUTER)
+whoseTurn = HUMAN;
+else if (whoseTurn == HUMAN)
+whoseTurn = COMPUTER;
+declareWinner(whoseTurn);
+}
+}
+int main()
+{
+printf("\n-------------------------------------------------------------------\n\n");
+printf("\t\t\t Tic-Tac-Toe\n");
+printf("\n-------------------------------------------------------------------\n\n");
+char cont='y';
+do {
+char choice;
+printf("Do you want to start first?(y/n) : ");
+scanf(" %c", &choice);
+if(choice=='n')
+playTicTacToe(COMPUTER);
+else if(choice=='y')
+playTicTacToe(HUMAN);
+else
+printf("Invalid choice\n");
+printf("\nDo you want to quit(y/n) : ");
+scanf(" %c", &cont);
+} while(cont=='n');
+return (0);
+}