while循环

求100之和

#!/usr/bin/env python
# _*_ coding:utf-8 _*_
i = 0
sum = 0
while i < 100:
    i = i + 1
    sum = sum + i
    print(sum）

　　

打印1-100跳过7

#!/usr/bin/env python
# _*_ coding:utf-8 _*_
i = 0
while i < 10:
    i = i + 1
    if i == 7:
        pass
    else:
        print(i)

　　

#!/usr/bin/env python
# _*_ coding:utf-8 _*_
i = 1
while i < 10:
    i = i + 1
    if i == 7:
        continue
    print(i)

打印奇偶数

#!/usr/bin/env python
# _*_ coding:utf-8 _*_
i = 0
while i < 100:
    i = i + 1
    if i%2 == 0:
        print("偶数", i)
    else:
        print("奇数", i)

 

限制登陆次数3次

#!/usr/bin/env python
# _*_ coding:utf-8 _*_
log_count = 0
while log_count < 3:
    login = input("enter your name")
    log_count = log_count + 1
    if login == "ali":
        print("bingo")
        break
    elif log_count == 3:
        print("max count = 3")
    else:
        print("error try ag")