basic tic tac toe

Question

I looked a little into HTML a year ago but decided to try python yesterday and came up with this for tic-tac-toe. I have no programming experience and I haven't yet looked at other peoples versions of tic-tac-toe as I wanted to see if I could do it myself, there's definitely a lot of ways I could have been more efficient that I notice but in terms of general bad code writing habits that you might see input would be very welcome.

turn = 2
winner = 0
gamestate = 0
row1 =[]
row2 =[]
row3 =[]
rowlist =[row1,row2,row3]
gamestate = 1
#arbitraryvalues
xrow1alt = [3,6,9]
xrow2alt = [2,5,8]
xrow3alt = [1,4,7]
orow1alt = [3,6,9]
orow2alt = [2,5,8]
orow3alt = [1,4,7]
xaltrows = [xrow1alt,xrow2alt,xrow3alt]
oaltrows = [orow1alt,orow2alt,orow3alt]
def printboard():
    print(*row1, sep="")
    print(*row2, sep="")
    print(*row3, sep="")
def drawboard():
    for i in range(3):
        row1.append('-')
        row2.append('-')
        row3.append('-')
#fix turn and consolidate inputs
def controls():
    global turn
    if turn == 2:
        playerturn = 'x'
        playernum = 1
    if turn == 1:
        playerturn = 'o'
        playernum = 2
    if playernum == 1:
        rownum = int(input("player 1's turn, select row "))
        columnnum = int(input("player 1's turn, select clumn "))
    if playernum == 2:
        rownum = int(input("player 2's turn, select row "))
        columnnum = int(input("player 2's turn, select clumn "))
    if rownum == 1:
        row1.pop(columnnum-1)
        row1.insert(columnnum-1,playerturn)
        if playernum == 1:
            xrow1alt.pop(columnnum-1)
            xrow1alt.insert(columnnum-1,playerturn)
        else:
            orow1alt.pop(columnnum-1)
            orow1alt.insert(columnnum-1,playerturn)
    if rownum == 2:
        row2.pop(columnnum-1)
        row2.insert(columnnum-1,playerturn)
        if playernum == 1:
            xrow2alt.pop(columnnum-1)
            xrow2alt.insert(columnnum-1,playerturn)
        else:
            orow2alt.pop(columnnum-1)
            orow2alt.insert(columnnum-1,playerturn)
    if rownum == 3:
        row3.pop(columnnum-1)
        row3.insert(columnnum-1,playerturn)
        if playernum == 1:
            xrow3alt.pop(columnnum-1)
            xrow3alt.insert(columnnum-1,playerturn)
        else:
            orow3alt.pop(columnnum-1)
            orow3alt.insert(columnnum-1,playerturn)
    if playerturn =='x':
        turn = 1
    if playerturn =='o':
        turn = 2

def wincheck():
    global winner
    xtotal = 0
    ototal = 0
    global gamestate
    y = 0
    for i in xaltrows:
        xvalues = [159,150,141,147,153]
        for x in range(len(i)):
            if i[x] == 'x':
                i[x] = 40
    xtotal = sum(xrow1alt) + sum(xrow2alt) + sum(xrow3alt)
    print(xtotal)
    if xtotal in xvalues:
        winner = 1
        gamestate +=1
    for i in oaltrows:
        ovalues = [276,279,282,288,270]
        for x in range(len(i)):
            if i[x] == 'o':
                i[x] = 83
    ototal = sum(orow1alt) + sum(orow2alt) + sum(orow3alt)
    if ototal in ovalues:
        winner +=2
        gamestate +=1
drawboard()
printboard()
while gamestate == 1:
    controls()
    printboard()
    wincheck()
print("winner is player ",winner)

Answer 1

See PEP 8 -- Style Guide for Python Code

Add some empty lines to make it more readable - ie. before every def.
And sometimes before if or for.

Add spaces after , to make code readable.

All global put at the beginning of function - it helps to see what external variables function will use.

All functions put at the beginning - before turn = 2

You could use else instead of some if - to make code simpler.

You keep rows in rowlist so you could use for-loop to display rows.

You could also keep xaltrows and oaltrows on list or dictionary and use turn to select values.

gamestate could use True/False instead of 0, 1

---

I saw one problem - player can select place which is already used and it changes o into x.

I didn't try to find other problems.

---

def printboard():
    for row in rowlist:
        print(*row, sep="")
    
def drawboard():
    for i in range(3):
        for row in rowlist:
            row.append('-')
        
def controls():
    global turn
    
    if turn == 2:
        playerturn = 'x'
        playernum = 1
    else:
        playerturn = 'o'
        playernum = 2

    if playernum == 1:
        rownum = int(input("player 1's turn, select row "))
        columnnum = int(input("player 1's turn, select clumn "))
    else:
        rownum = int(input("player 2's turn, select row "))
        columnnum = int(input("player 2's turn, select clumn "))

    if rownum == 1:
        row1.pop(columnnum-1)
        row1.insert(columnnum-1, playerturn)
        if playernum == 1:
            xrow1alt.pop(columnnum-1)
            xrow1alt.insert(columnnum-1, playerturn)
        else:
            orow1alt.pop(columnnum-1)
            orow1alt.insert(columnnum-1, playerturn)
    elif rownum == 2:
        row2.pop(columnnum-1)
        row2.insert(columnnum-1, playerturn)
        if playernum == 1:
            xrow2alt.pop(columnnum-1)
            xrow2alt.insert(columnnum-1, playerturn)
        else:
            orow2alt.pop(columnnum-1)
            orow2alt.insert(columnnum-1, playerturn)
    elif rownum == 3:
        row3.pop(columnnum-1)
        row3.insert(columnnum-1, playerturn)
        if playernum == 1:
            xrow3alt.pop(columnnum-1)
            xrow3alt.insert(columnnum-1, playerturn)
        else:
            orow3alt.pop(columnnum-1)
            orow3alt.insert(columnnum-1, playerturn)

    if playerturn =='x':
        turn = 1
    else:
        turn = 2

def wincheck():
    global winner
    global gamestate
    
    xtotal = 0
    ototal = 0
    y = 0
    
    for i in xaltrows:
        xvalues = [159, 150, 141, 147, 153]
        for x in range(len(i)):
            if i[x] == 'x':
                i[x] = 40
                
    xtotal = sum(xrow1alt) + sum(xrow2alt) + sum(xrow3alt)
    print('xtotal:', xtotal)
    
    if xtotal in xvalues:
        winner = 1
        gamestate = False
        
    for i in oaltrows:
        ovalues = [276, 279, 282, 288, 270]
        for x in range(len(i)):
            if i[x] == 'o':
                i[x] = 83
                
    ototal = sum(orow1alt) + sum(orow2alt) + sum(orow3alt)
    
    if ototal in ovalues:
        winner +=2
        gamestate = False

# --- main ---

turn = 2
winner = 0
gamestate = True

row1 = []
row2 = []
row3 = []

rowlist = [row1, row2, row3]

#arbitraryvalues
xrow1alt = [3,6,9]
xrow2alt = [2,5,8]
xrow3alt = [1,4,7]
orow1alt = [3,6,9]
orow2alt = [2,5,8]
orow3alt = [1,4,7]

xaltrows = [xrow1alt,xrow2alt,xrow3alt]
oaltrows = [orow1alt,orow2alt,orow3alt]

drawboard()
printboard()

while gamestate:
    controls()
    printboard()
    wincheck()
    
print("winner is player", winner)
```