Python练习-跳出多层循环和购物车
跳出多层循环:三层循环,最里层直接跳出3层
在Python中,函数运行到return这一句就会停止,因此可以利用这一特性,将功能写成函数,终止多重循环
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def
work():
for
i
in
range
(
5
):
print
(
"i="
, i)
for
j
in
range
(
5
):
print
(
"--j="
, j)
for
k
in
range
(
5
):
if
k<
2
:
print
(
"------>k="
, k)
else
:
return
i,j,k
print
(work())
|
注:后面对此进行更新拓展,链接如下:
http://www.cnblogs.com/xuyaping/p/6639830.html
购物车程序
需求:1.启动程序后,让用户输入工资,然后打印商品列表
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2.允许用户根据商品编号购买商品
3.用户选择商品后,检测余额是否够,够就直接扣款,不够就提醒
4.可随时退出,退出时,打印已购买商品和余额
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salary
=
int
(
input
(
"input your salary:"
))
#输入工资
balance
=
salary
#将工资赋值给余额
products
=
[
"book"
,
"coffe"
,
"cake"
,
"iphone"
]
#定义可购买商品
price
=
[
40
,
20
,
30
,
2000
]
#定义商品价格
print
(
"number "
,
"products "
,
"price"
)
#输出商品列表第一行
products_buy
=
[]
#设置购物车商品列表
for
i
in
range
(
len
(products)):
#输出商品列表产品及价格
print
(i
+
1
,
"\t\t"
,products[i],
"\t\t"
, price[i])
print
(
"q"
,
"\t\t"
,
"quit"
)
#输出“q”指令打印命令“quit”(退出)
while
True
:
number
=
input
(
"input your products_number:"
)
if
number!
=
"q"
:
#若输入的不是“q”,则为整型,循环打印已购买商品和余额
number_
=
int
(number)
if
balance >
=
price[number_
-
1
]:
balance
-
=
price[number_
-
1
]
products_buy.append(products[number_
-
1
])
print
(
"products_buy is"
,products_buy,
",balance is "
,balance)
else
:
print
(
"余额不足!"
)
else
:
#输入的为“q”,打印已购买商品和余额
print
(
"products_buy is"
, products_buy,
",balance is "
, balance)
break
|
运行程序:
跳出多层循环:三层循环,最里层直接跳出3层
在Python中,函数运行到return这一句就会停止,因此可以利用这一特性,将功能写成函数,终止多重循环
1
2
3
4
5
6
7
8
9
10
11
12
13
14
|
def
work():
for
i
in
range
(
5
):
print
(
"i="
, i)
for
j
in
range
(
5
):
print
(
"--j="
, j)
for
k
in
range
(
5
):
if
k<
2
:
print
(
"------>k="
, k)
else
:
return
i,j,k
print
(work())
|
注:后面对此进行更新拓展,链接如下:
http://www.cnblogs.com/xuyaping/p/6639830.html
购物车程序
需求:1.启动程序后,让用户输入工资,然后打印商品列表
2.允许用户根据商品编号购买商品
3.用户选择商品后,检测余额是否够,够就直接扣款,不够就提醒
4.可随时退出,退出时,打印已购买商品和余额
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
|
salary
=
int
(
input
(
"input your salary:"
))
#输入工资
balance
=
salary
#将工资赋值给余额
products
=
[
"book"
,
"coffe"
,
"cake"
,
"iphone"
]
#定义可购买商品
price
=
[
40
,
20
,
30
,
2000
]
#定义商品价格
print
(
"number "
,
"products "
,
"price"
)
#输出商品列表第一行
products_buy
=
[]
#设置购物车商品列表
for
i
in
range
(
len
(products)):
#输出商品列表产品及价格
print
(i
+
1
,
"\t\t"
,products[i],
"\t\t"
, price[i])
print
(
"q"
,
"\t\t"
,
"quit"
)
#输出“q”指令打印命令“quit”(退出)
while
True
:
number
=
input
(
"input your products_number:"
)
if
number!
=
"q"
:
#若输入的不是“q”,则为整型,循环打印已购买商品和余额
number_
=
int
(number)
if
balance >
=
price[number_
-
1
]:
balance
-
=
price[number_
-
1
]
products_buy.append(products[number_
-
1
])
print
(
"products_buy is"
,products_buy,
",balance is "
,balance)
else
:
print
(
"余额不足!"
)
else
:
#输入的为“q”,打印已购买商品和余额
print
(
"products_buy is"
, products_buy,
",balance is "
, balance)
break
|
运行程序: