Python（3）-循环语句：从最内层跳出多层循环
跳出多层循环：三层循环，最里层直接跳出3层
方法一：
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():
#定义函数
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())
|
方法二：
定义变量，更改变量状态，不满足条件，循环跳出
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break_flag
=
False
for
i
in
range
(
10
):
print
(
"爷爷层"
)
for
j
in
range
(
10
):
print
(
"爸爸层"
)
for
k
in
range
(
10
):
print
(
"孙子层"
)
if
k
=
=
3
:
break_flag
=
True
break
#跳出孙子层循环，继续向下运行
if
break_flag
=
=
True
:
break
#满足条件，运行break跳出爸爸层循环，向下运行
if
break_flag
=
=
True
:
break
#满足条件，运行break跳出爷爷层循环，结束全部循环，向下运行
print
(
"keep going..."
)
|
方法三：
while循环语句，定义条件，条件改变，循环结束
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break_flag
=
False
count
=
0
while
break_flag
=
=
False
:
print
(
"爷爷层..."
)
while
break_flag
=
=
False
:
print
(
"爸爸层..."
)
while
break_flag
=
=
False
:
if
count<
5
:
print
(
"孙子层..."
)
count
+
=
1
else
:
break_flag
=
True
print
(
"keep going..."
)
|
跳出多层循环：三层循环，最里层直接跳出3层
方法一：
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():
#定义函数
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())
|
方法二：
定义变量，更改变量状态，不满足条件，循环跳出
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
|
break_flag
=
False
for
i
in
range
(
10
):
print
(
"爷爷层"
)
for
j
in
range
(
10
):
print
(
"爸爸层"
)
for
k
in
range
(
10
):
print
(
"孙子层"
)
if
k
=
=
3
:
break_flag
=
True
break
#跳出孙子层循环，继续向下运行
if
break_flag
=
=
True
:
break
#满足条件，运行break跳出爸爸层循环，向下运行
if
break_flag
=
=
True
:
break
#满足条件，运行break跳出爷爷层循环，结束全部循环，向下运行
print
(
"keep going..."
)
|
方法三：
while循环语句，定义条件，条件改变，循环结束
|
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2
3
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7
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12
13
14
15
|
break_flag
=
False
count
=
0
while
break_flag
=
=
False
:
print
(
"爷爷层..."
)
while
break_flag
=
=
False
:
print
(
"爸爸层..."
)
while
break_flag
=
=
False
:
if
count<
5
:
print
(
"孙子层..."
)
count
+
=
1
else
:
break_flag
=
True
print
(
"keep going..."
)
|