day1

#输出 1-100 内的所有偶数

n = 1
while n <= 101:
    if n%2 == 0:
        print(n)
    else:
        pass
    n +=1

　　

#使用while循环输入 1 2 3 4 5 6     8 9 10
n = 1
while n < 11:
    if n == 7:
        pass
    else:
      print(n)
    n = n + 1#n是在全局的位置，不是在某个代码块的位置

#输出 1-100 内的所有奇数
n = 1
while n < 101:
    if n%2 == 0:
        pass
    else:
        print(n)
    n = n + 1

#计算1-100所有数的和
n = 1
s = 0
while n < 101:
    temp = n % 2
    if temp == 0:
        s = s - n
    else:
        s = s + n
   
    n = n + 1
print(s)

#用户登陆（三次机会重试）
name1 = "jack"
password1 = "123"
n = 1
m = 3
while True:
    username = input("please input your name: ")
    userpassword = input("please input your password: ")
    if username == name1 and userpassword == password1:
        print("%s,欢迎登陆"%username)
        exit()
    else:
        if n > 2:
            print("输入错误3次，退出系统")
            exit()
        else:
            m  = m - 1
            print("输入错误%s次"%n)
        n = n + 1