#while语法,while循环又称为条件循环
# while 条件:
# code1
# code2
# code3
# ....
# user_db='egon'
# pwd_db='123'
#
# while True:
# inp_user=input('username>>: ')
# inp_pwd=input('password>>: ')
# if inp_user == user_db and inp_pwd == pwd_db:
# print('login successfull')
# else:
# print('user or password error')
#2 while+break:break的意思是终止掉当前层的循环,.执行其他代码
# while True:
# print('1')
# print('2')
# break
# print('3')
# user_db='egon'
# pwd_db='123'
#
# while True:
# inp_user=input('username>>: ')
# inp_pwd=input('password>>: ')
# if inp_user == user_db and inp_pwd == pwd_db:
# print('login successfull')
# break
# else:
# print('user or password error')
# print('其他代码')
#3 while+continue:continue的意思是终止掉本次循环,.直接进入下一次循环
#ps:记住continue一定不要加到循环体最后一步执行的代码
# n=1
# while n <= 10: #
# if n == 8:
# n += 1 #n=9
# continue
# print(n)
# n+=1 #n=11
# while True:
# if 条件1:
# code1
# code2
# code3
# continue #无意义
# elif 条件1:
# code1
# continue #有意义
# code2
# code3
# elif 条件1:
# code1
# code2
# code3
# continue #无意义
# ....
# else:
# code1
# code2
# code3
# continue #无意义
#while循环嵌套
# user_db='egon'
# pwd_db='123'
#
# while True:
# inp_user=input('username>>: ')
# inp_pwd=input('password>>: ')
# if inp_user == user_db and inp_pwd == pwd_db:
# print('login successfull')
# while True:
# cmd=input('请输入你要执行的命令: ')
# if cmd == 'q':
# break
# print('%s 功能执行...' %cmd)
# break
# else:
# print('user or password error')
#
#
# print('end....')
#
#while+tag
# user_db='egon'
# pwd_db='123'
#
# tag=True
# while tag:
# inp_user=input('username>>: ')
# inp_pwd=input('password>>: ')
# if inp_user == user_db and inp_pwd == pwd_db:
# print('login successfull')
# while tag:
# cmd=input('请输入你要执行的命令: ')
# if cmd == 'q':
# tag=False
# else:
# print('%s 功能执行...' %cmd)
#
# else:
# print('user or password error')
# print('end....')
#while+else (***)
#
# n=1
# while n < 5:
# # if n == 3:
# # break
# print(n)
# n+=1
# else:
# print('在整个循环结束后,会进行判断:只有while循环在没有被break结束掉的情况下才会执行else中的代码')
