python实现简单的井字棋

import random
board = [['+','+','+'],['+','+','+'],['+','+','+']]
def ma(board):
    if isempty(board):
        a = random.randint(0, 2)
        b = random.randint(0, 2)
        if board[a][b] != 'X' and board[a][b] != 'O':
            print("机器走：")
            board[a][b] = 'O'
            oput(board)
        else:
            ma(board)
    else:
        print("平局")
def oput(board):
    print("  0 1 2")
    for i in range(3):
        print(i, end=' ')
        for j in range(3):
            print(board[i][j], end=" ")
        print("")
def winput(i,j):
    if board[i][j] == 'X':
        print("human win")
    else:
        print("machine win")
    return 1

def test(board):
    for i in range(3):
        for j in range(3):
            if board[i][j] != '+':
                if j == 0:
                    if board[i][j] == board[i][j + 1] == board[i][j + 2]:
                        return winput(i,j)
                if i == 0:
                    if board[i][j] == board[i + 1][j] == board[i + 2][j]:
                        return winput(i,j)
                if i == 0 and j == 0:
                    if board[i][j] == board[i + 1][j + 1] == board[i + 2][j + 2]:
                        return winput(i,j)
                if i == 2 and j == 0:
                    if board[i][j] == board[i - 1][j + 1] == board[i - 2][j + 2]:
                        return winput(i,j)

def isempty(board):
    for i in range(3):
        for j in range(3):
            if board[i][j] == '+':
                return True
    return False
def main():
    print("初始棋盘：")
    oput(board)
    flag = 0
    t = input("human first? Y/N  human for X, machine for O\n")
    if t == 'Y':
        while isempty(board):
            print("人走：  ")
            a, b = map(int, input("输入落子纵横坐标： a,b \n").split(','))
            if board[a][b] == '+':
               board[a][b] = 'X'
               oput(board)
               flag = test(board)
               if flag == 1:
                  break
            else:
                print("落子位置不对")
                continue
            ma(board)
            flag = test(board)
            if flag == 1:
                break
            if isempty(board) == 0 and flag == 0:
                print("平局")
                break
    elif t == 'N':
        while isempty(board):
            ma(board)
            flag = test(board)
            if isempty(board) == 0 and flag == 0:
                print("平局")
                break
            if flag == 1:
                break
            print("人走：  ")
            a, b = map(int, input("输入落子纵横坐标： a,b \n").split(','))
            if board[a][b] == '+':
                board[a][b] = 'X'
                oput(board)
                flag = test(board)
                if flag == 1:
                    break
            else:
                print("落子位置不对")
                continue

if __name__ == "__main__":
    main()