Python学习之路3?while循环

Posted 2020-08-30

#_*_coding:utf-8_*_
#!/usr/bin/env python
count=0
# while count<10:
# print(‘==>‘,count)
# count+=1

# while True:
# print(‘------‘)

# for i in range(10):
# print(i)

# for i in ‘hello‘:
# print(i)

# msg=‘hello‘
# i=0
# while i<len(msg):
# print(msg[i])
# i+=1

# while 1:
# print(‘ok‘)

#循环的嵌套

# while True:
# name=input(‘username: ‘)
# if name == ‘quit‘:break
#
# print(name)
# while True:
# age=input(‘age: ‘)
#
# if age == ‘quit‘:break
#
# print(age)

# for i in range(5):
# print(‘=======第一层for‘)
# for j in range(2):
# print(‘--->‘)
# break
# print(‘->‘)

 

‘‘‘
‘第一层for‘
‘第二层for‘
‘第二层for‘

‘第一层for‘
‘第二层for‘
‘第二层for‘

 

‘‘‘

#标志位
# import sys
tag=True
while tag:
a=input("level1")
if a == ‘q‘: break
while tag:
b = input("level2")
if b == ‘q‘: break
while tag:
c=input(‘level3‘)
if c == ‘q‘: break
while tag:
d=input(‘level4‘)
if d == ‘q‘:break
# if d==‘exit‘:sys.exit()
if d == ‘exit‘:tag=False

print(‘====>‘)