#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')
