Python学习【day01】- Python初识-练习

9.1 使用while循环输出 1 2 3 4 5 6     8 9 10

 1 #!/usr/bin/env python
 2 # -*- coding:utf8 -*-
 3 
 4 n = 1;
 5 
 6 while n < 11 :
 7     if n == 7 :
 8         pass
 9     else :
10         print(n)
11     n = n + 1

9.2 求1-100的和

1 #!/usr/bin/env python
2 # -*- coding:utf8 -*-
3 
4 n = 1
5 s = 0
6 while n < 101 :
7     s = s + n
8     n = n + 1
9 print(s)

9.3 输出 1-100 内的所有奇数

1 #!/usr/bin/env python
2 # -*- coding:utf8 -*-
3 
4 n = 1
5 
6 while n < 101 :
7     if n % 2 == 1 :
8         print(n)
9     n = n + 1

9.4 输出 1-100 内的所有偶数

1 #!/usr/bin/env python
2 # -*- coding:utf8 -*-
3 
4 n = 1
5 
6 while n < 101 :
7     if n % 2 == 0 :
8         print(n)
9     n = n + 1

9.5 求1-2+3-4+5 ... 99的和

 1 #!/usr/bin/env python
 2 # -*- coding:utf8 -*-
 3 
 4 n = 1
 5 s = 0
 6 
 7 while n < 100 :
 8     if n % 2 == 0 :
 9         s = s - n
10     else :
11         s = s + n
12     n = n + 1
13 print(s)

9.6 前面的用户登录(可以有三次登录机会)

 1 #!/usr/bin/env python
 2 # -*- coding:utf8 -*-
 3 
 4 print("你有三次输入机会")
 5 
 6 n = 1
 7 
 8 while n < 4 :
 9     name = input("请输入用户名：")
10     password = input("请输入密码：")
11     
12     if name == "root" :
13         if password == "123456" :
14             print("登录成功")
15             break
16         else :
17             print("第" , n , "次，密码错误")
18     else :
19         print("第" , n , "次，用户名错误")
20     if n == 3 :
21         print("你已输错三次,异常退出")
22     n = n + 1