How to fix tic-tac-toe two player bug

Question

I am trying to make a tic-tac-toe game however when I try implement two players, the printed out result (current game state) is not as expected. for example when I try to put the letter 'x' in box 1 it will add random letters/numbers in different spots. I have already tried this with only one player and it wrks perfectly.

import random
a = ' '
b = ' '
c = ' '
d = ' '
e = ' '
f = ' '
g = ' '
h = ' '
i = ' '
def gamestateboard(a, b, c, d, e, f, g, h, i):
    x = [a, b, c]
    y = [d, e, f]
    z = [g, h, i]

    print(x)
    print(y)
    print(z)
gamestateboard(a, b, c, d, e, f, g, h, i)

def checkwin():
    if a == 0 and b == 0 and c == 0:
        print('Winner')
    if a == 0 and d == 0 and g == 0:
        print('Winner')
    if g == 0 and h == 0 and i == 0:
        print('Winner')
    if c == 0 and e == 0 and g == 0:
        print('Winner')
    if a == 0 and e == 0 and i == 0:
        print('Winner')
    if c == 0 and f == 0 and i == 0:
        print('Winner')



for i in range(1000000):
    inputs = str(input('Enter a position: '))
    if i%2 == 0:
        if inputs == '1':
            a = 0
            gamestateboard(a, b, c, d, e, f, g, h, i)
            checkwin()
        if inputs == '2':
            b = 0
            gamestateboard(a, b, c, d, e, f, g, h, i)
            checkwin()
        if inputs == '3':
            c = 0
            gamestateboard(a, b, c, d, e, f, g, h, i)
            checkwin()
        if inputs == '4':
            d = 0
            gamestateboard(a, b, c, d, e, f, g, h, i)
            checkwin()
        if inputs == '5':
            e = 0
            gamestateboard(a, b, c, d, e, f, g, h, i)
            checkwin()
        if inputs == '6':
            f = 0
            gamestateboard(a, b, c, d, e, f, g, h, i)
            checkwin()
        if inputs == '7':
            g = 0
            gamestateboard(a, b, c, d, e, f, g, h, i)
            checkwin()
        if inputs == '8':
            h = 0
            gamestateboard(a, b, c, d, e, f, g, h, i)
            checkwin()
        if inputs == '9':
            i = 0
            gamestateboard(a, b, c, d, e, f, g, h, i)
            checkwin()
else:
    if inputs == '1':
        a = 'X'
        gamestateboard(a, b, c, d, e, f, g, h, i)
        checkwin()
    if inputs == '2':
        b = 'X'
        gamestateboard(a, b, c, d, e, f, g, h, i)
        checkwin()
    if inputs == '3':
        c = 'X'
        gamestateboard(a, b, c, d, e, f, g, h, i)
        checkwin()
    if inputs == '4':
        d = 'X'
        gamestateboard(a, b, c, d, e, f, g, h, i)
        checkwin()
    if inputs == '5':
        e = 'X'
        gamestateboard(a, b, c, d, e, f, g, h, i)
        checkwin()
    if inputs == '6':
        f = 'X'
        gamestateboard(a, b, c, d, e, f, g, h, i)
        checkwin()
    if inputs == '7':
        g = 'X'
        gamestateboard(a, b, c, d, e, f, g, h, i)
        checkwin()
    if inputs == '8':
        h = 'X'
        gamestateboard(a, b, c, d, e, f, g, h, i)
        checkwin()
    if inputs == '9':
        i = 'X'
        gamestateboard(a, b, c, d, e, f, g, h, i)
        checkwin()

Answer 1

You are using i as your loop variable but also the name of a variable you use to draw in your game world.

I recommend moving away from having these variables and using indexes.

gameworld =[ [' ',' ',' '] for i in range(3)]

def draw_world():
    for i in range(3):
        print(gameworld[i])

then you can ask for coordinates or divide and use the modulus to use a single value like you did before. 4 // 3 = 1 4 % 3 = 1 position 4 is at [1][1]

This means you don't need your giant if input == list.

edit: Oh yeah you probably also want to do a loop with something like

no_winner = True
while no_winner:
    ...

you can set no_winner to False if check_win returns true and then you game doens't go on forever

edit 2: Almost forgot you have an indenting error with the else for i%2==0 though I'm guessing that may be just from when you copied and pasted into your question. You also never check to see if someone else has already taken a square so when your code does actually work a player can overwrite another player's move.