这个教程，我们将展示如何用python创建一个井字游戏。 其中我们将使用函数、数组、if条件语句、while循环语句和错误捕获等。
首先我们需要创建两个函数，第一个函数用来显示游戏板:
def print_board():
for i in range(0,3):
for j in range(0,3):
print map[2-i][j],
if j != 2:
print "|",
print ""
这我们使用两个for循环来遍历map，该map是一个包含了位置信息的二维数组。
游戏板看起来是这样的:
| | | | | | X | X | O | X | O | O | X X | X | X X | X | X X | X | X
下面我们需要一个函数check_done()来检查游戏是否结束。如果结束，则返回True并打印消息。
def check_done():
for i in range(0,3):
if map[i][0] == map[i][1] == map[i][2] != " " or map[0][i] == map[1][i] == map[2][i] != " ":
print turn, "won!!!"
return True
if map[0][0] == map[1][1] == map[2][2] != " " or map[0][2] == map[1][1] == map[2][0] != " ":
print turn, "won!!!"
return True
if " " not in map[0] and " " not in map[1] and " " not in map[2]:
print "Draw"
return True
return False
有几个地方需要检查，首先检查水平和垂直方向，是否有一行或一列不为空且包含有三个相同的符号，然后我们再检查斜方向。如果上面有一个方向满足，游戏结束并打印“Won!!!”。请注意检查变量改变，它用来标记当前是哪一位玩家。
同时我们需要检查当前游戏板是否被填满且没有人获胜，游戏平局。
有了上面的两个函数，下面我们创建3个变量:
turn = "X"
map = [[" "," "," "],
[" "," "," "],
[" "," "," "]]
done = False
turn : 轮到谁
map : 游戏板
done : 游戏是否结束
现在启动游戏:
while done != True: print_board() print turn, "'s turn" print moved = False while moved != True:
这里使用了while循环直到游戏结束并返回true.在这个循环里面，使用了另外一个while循环来检查玩家是否移动，如果玩家没有移动，则程序会跳到下一次循环。
下一步告诉玩家怎么玩:
print "Please select position by typing in a number between 1 and 9, see below for which number that is which position..."
print "7|8|9"
print "4|5|6"
print "1|2|3"
print
try:
pos = input("Select: ")
if pos <=9 and pos >=1:
我们期望玩家输入一个数字，检查该数字是否是在1到9之间。另外，我们这里需要一段错误处理逻辑，我们还需要需要检查玩家是否能移动到一个位置:
Y = pos/3
X = pos%3
if X != 0:
X -=1
else:
X = 2
Y -=1
以下是全部的代码:
def print_board():
for i in range(0,3):
for j in range(0,3):
print map[2-i][j],
if j != 2:
print "|",
print ""
def check_done():
for i in range(0,3):
if map[i][0] == map[i][1] == map[i][2] != " " or map[0][i] == map[1][i] == map[2][i] != " ":
print turn, "won!!!"
return True
if map[0][0] == map[1][1] == map[2][2] != " " or map[0][2] == map[1][1] == map[2][0] != " ":
print turn, "won!!!"
return True
if " " not in map[0] and " " not in map[1] and " " not in map[2]:
print "Draw"
return True
return False
turn = "X"
map = [[" "," "," "],
[" "," "," "],
[" "," "," "]]
done = False
while done != True:
print_board()
print turn, "'s turn"
print
moved = False
while moved != True:
print "Please select position by typing in a number between 1 and 9, see below for which number that is which position..."
print "7|8|9"
print "4|5|6"
print "1|2|3"
print
try:
pos = input("Select: ")
if pos <=9 and pos >=1:
Y = pos/3
X = pos%3
if X != 0:
X -=1
else:
X = 2
Y -=1
if map[Y][X] == " ":
map[Y][X] = turn
moved = True
done = check_done()
if done == False:
if turn == "X":
turn = "O"
else:
turn = "X"
except:
print "You need to add a numeric value"