#1、使用while循环输出1 2 3 4 5 6     8 9 10

# s=0

# while s<10:

#     s+=1

#     if s==7:

#         continue

#     print(s)

# for i in range(1,11):

#     if i==7:

#         continue

#     print(i)

#     i += 1

#2、求1-100的所有数的和

# s=0

# i=0

# while i<100:

#     i+=1

#     s+=i

# print(s)

# s=0

# for i in range(1,101):

#     s+=i

# print(s)

#3、输出 1-100 内的所有奇数

# s=0

# while s<100:

#     s+=1

#     if s%2==1:

#         print(s)

# for i in range(1,101):

#     if i%2==1:

#         print(i)

#4、输出 1-100 内的所有偶数

# s=0

# while s<100:

#     s+=1

#     if s%2==0:

#         print(s)

# for i in range(1,101):

#     if i%2==0:

#         print(i)

#5、求1-2+3-4+5 ... 99的所有数的和

# s=0

# i=1

# while i<100:

#     if i%2==1:

#         s+=i

#     elif i%2==0:

#         s-=i

#     i+=1

# print(s)

# s=0

# for i in range(1,100):

#     if i%2==1:

#         s+=i

#     elif i%2==0:

#         s-=i

# print(s)

#6、用户登陆（三次机会重试）

# count=0

# while count<3:

#     name=input('请输入用户名 ')

#     passwd=input('请输入密码 ')

#     if name=='z' and passwd=='123':

#         print('登录成功')

#         break

#     else:

#         print('用户名密码错误')

#         count+=1

# 改进版

# user='z'

# pwd='123'

# count=0

# while count<3:

#     username=input('请输入用户名 ')

#     if username == user:

#         passwd=input('请输入密码 ')

#         if  passwd==pwd:

#             print('登陆成功')

#             break

#         else:

#             print('密码错误，请重新输入')

#             continue

#     else:

#         count += 1

#         print('用户名错误,请重新输入')

# else:

#     print('您输错了3次，已锁定')