Added tic tac toe game in python

Python/Tic_Tac_Toe_game.py

@@ -0,0 +1,110 @@
+def user1turn(board): #user 1 turn
+    pos=int(input("enter x position:"))
+    if(board[pos-1]!=0):
+        print("wrong move")
+        exit(0)
+    board[pos-1]=-1
+
+def user2turn(board): #user 2 turn
+    pos=int(input("enter O position:"))
+    if(board[pos-1]!=0):
+        print("wrong move")
+        exit(0) #if wrong move then program ends
+    board[pos-1]=1
+
+def displayboard(board): #this function used to print the board
+    for i in range(0,9):
+        if((i>0) and (i%3==0)):
+            print("\n")
+        if(board[i]==0):#0=empty
+            print("_ ",end=" ")
+        if(board[i]==1):#1=O
+            print("O",end=" ")
+        if(board[i]==-1):#-1=X
+            print('X',end=" ")
+    print("\n")
+
+
+
+def analyzeboard(board): #this function used to find out if somebody has won or not
+    cb=[[0,1,2],[3,4,5,],[6,7,8],[0,3,6],[1,4,7],[2,5,8],[0,4,8],[2,4,6]]#all combinations of winning
+    for i in range(0,8):
+        if((board[cb[i][0]]!=0) and (board[cb[i][1]]==board[cb[i][2]]) and (board[cb[i][0]]==board[cb[i][1]])):
+            return board[cb[i][0]]#if somebody won
+
+    return(0)#if no one won
+
+def minmax(board,player):
+    x=analyzeboard(board)
+    if(x!=0):
+        return (x*player)
+    pos=-1
+    value=-2
+    for i in range(0,9):
+        if(board[i]==0):
+            board[i]=player
+            score=-minmax(board, player*-1)
+            board[i]=0
+            if(score>value):
+                value=score
+                pos=i
+    if(pos==-1):
+        return 0
+    return value
+
+
+
+def computerturn(board):
+    pos=-1
+    value=-2
+    for i in range(0,9):
+        if(board[i]==0):
+            board[i]=1
+            score=-minmax(board, -1)
+            board[i]=0
+            if(score>value):
+                value=score
+                pos=i
+    board[pos]=1
+
+
+
+
+def main():
+    choice=int(input("enter 1 for single player and 2 for multiplayer:"))
+    board=[0,0,0,0,0,0,0,0,0] #mathmatical representation of gameboard
+    if(choice==1):
+        player=int(input("enter 1 to play first and 2 to play second:"))
+        for i in range(0,9):
+            if(analyzeboard(board)!=0):
+                break
+            if((i+player)%2==0):
+                computerturn(board)
+            else:
+                displayboard(board)
+                user1turn(board)
+
+    else:
+        for i in range(0,9):
+            if(analyzeboard(board)!=0):#checking if somebody has won or not
+                break#if somebody then show final result
+            else:
+                if(i%2==0):#even numbers(0,4..) are user1 turn
+                    displayboard(board)#will show gameboard after every step
+                    user1turn(board)
+                else:       #odd numbers(1,3,..) are user2 turn
+                    displayboard(board)
+                    user2turn(board)
+
+        x=analyzeboard(board) #code for multiplayer
+        if(x==0):
+            displayboard(board)
+            print("draw")
+        if(x==1):
+            displayboard(board)
+            print("play O won")
+        if(x==-1):
+            displayboard(board)
+            print("play X won")
+main()
+