Added the code for tic-tac-toe game with unbeatable AI

Python Beginners/AI-tic-tac-toe.py

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+import random
+import time
+
+
+# For displaying the game board
+def display(grid):
+    for row in range(3):
+        print(" | ", end="")
+        for column in range(3):
+            if grid[row][column] == 0:
+                print(" ", end="")
+            else:
+                print(grid[row][column], end="")
+            print(" | ", end="")
+        print("")
+
+
+# For checking available moves
+def available_moves(grid):
+    moves = []
+    for row in range(3):
+        for column in range(3):
+            if grid[row][column] not in ["X", "O"]:
+                moves.append(grid[row][column])
+    return moves
+
+
+# For checking who's the winner
+def check_winner(grid, player):
+    # Checking for row or column win
+    for i in range(3):
+        if all(grid[i][j] == player for j in range(3)) or all(
+                grid[j][i] == player for j in range(3)):
+            return True
+
+    # Checking for diagonal win
+    if all(grid[i][i] == player for i in range(3)) or all(grid[i][2 - i] == player for i in range(3)):
+        return True
+
+    return False
+
+
+# For checking whether the board is full
+def no_move_remaining(grid):
+    count = 0
+    for row in range(3):
+        for column in range(3):
+            if grid[row][column] in ["X", "O"]:
+                count = count + 1
+    if count == 9:
+        return True
+    return False
+
+
+def make_move(positions, pattern, position, move):
+    for row in range(3):
+        for column in range(3):
+            if positions[row][column] == position:
+                pattern[row][column] = move
+                return True
+    return False
+
+
+# Unbeatable AI player
+def ai_move(positions, pattern):
+    # Checking for available positions
+    available_positions = available_moves(positions)
+
+    # Checking two-way win situation
+    if 1 not in available_positions and 9 not in available_positions and len(available_positions) == 6:
+        return random.choice([2, 8])
+
+    if 3 not in available_positions and 7 not in available_positions and len(available_positions) == 6:
+        return random.choice([4, 6])
+
+    # Checking for a winning move
+    for position in available_positions:
+        temp_pattern = [row[:] for row in pattern]
+        if make_move(positions, temp_pattern, position, "O") and check_winner(temp_pattern, "O"):
+            return position
+
+    # If no winning move, checking to block user's move
+    for position in available_positions:
+        temp_pattern = [row[:] for row in pattern]
+        if make_move(positions, temp_pattern, position, "X") and check_winner(temp_pattern, "X"):
+            return position
+
+    # Strategic moves
+    strategic_moves = [5, 1, 3, 7, 9, 2, 4, 6, 8]
+    for position in strategic_moves:
+        if position in available_positions:
+            return position
+
+    # If no strategic move is possible, make a random move
+    return random.choice(available_positions)
+
+
+# Template for the positions on the board
+positions = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
+
+print("The position for each box is as follows : ")
+display(positions)
+
+pattern = [[0, 0, 0], [0, 0, 0], [0, 0, 0]]
+
+choice = input("Do you wish to start the game?(Y/N) : ")
+if choice == "Y":
+    chance = "user"
+else:
+    chance = "ai"
+
+while True:
+    # User's move
+    if chance == "user":
+        user_move = int(input("Enter your move position: "))
+        if user_move in available_moves(positions):
+            make_move(positions, pattern, user_move, "X")
+            make_move(positions, positions, user_move, "X")
+            display(pattern)
+            print()
+
+            if check_winner(pattern, "X"):
+                print("Congratulations! You win!")
+                break
+
+            elif no_move_remaining(pattern):
+                print("Its a tie!")
+                break
+
+            chance = "ai"
+
+        else:
+            print("Invalid move! Please enter an available position")
+            chance = "user"
+
+    # AI player's move
+    else:
+        print("AI player is thinking", end="")
+        time.sleep(0.2)
+        print(".",end="")
+        time.sleep(0.2)
+        print(".", end="")
+        time.sleep(0.2)
+        print(".")
+        time.sleep(0.3)
+        ai_position = ai_move(positions, pattern)
+        make_move(positions, pattern, ai_position, "O")
+        make_move(positions, positions, ai_position, "O")
+        display(pattern)
+        print()
+
+        if check_winner(pattern, "O"):
+            print("AI wins!")
+            break
+
+        elif no_move_remaining(pattern):
+            print("Its a tie!")
+            break
+
+        chance = "user"