#!/bin/bash/env python
# -*- coding:utf-8 -*-
#function:输出1-10每隔1秒

import time
start = 1
flag = True
while flag:
	print(start)
	if start > 9:
	  break
	else:
	  start = start + 1
	time.sleep(1)
	
print(‘end‘)
	

#!/bin/bash/env python
# -*- coding:utf-8 -*-
#function:输出1-10排除7

import time
start = 0

while True:
	start = start + 1
	if start == 7:
		continue
	elif start == 11:
		break
	else:
		print(start)
        time.sleep(1)
		
print(‘end‘)
		
		
		

#!/bin/bash/env python
# -*- coding:utf-8 -*-
#function:求1-100的所有数之和

sum=0
start=1
while True:
    sum = sum + start
    if start == 100:
        break
    start = start + 1
print(sum)

#!/bin/bash/env python
# -*- coding:utf-8 -*-
#function:输出1-100内所有的奇数

import time
start = 0
while True:
    start = start + 1
    if start % 2 == 0:
        continue
    if start == 99:
        break
    print(start)
    time.sleep(0.2)
print(‘end‘)

#!/bin/bash/env python
# -*- coding:utf-8 -*-
#function:输出1-100内所有的偶数

import time
start = 1
while True:
	start = start + 1
	if start % 2 != 0:
		continue
	if start == 102:
		break
	print(start)
	time.sleep(0.2)
print(‘end‘)

#!/bin/bash/env python
# -*- coding:utf-8 -*-
#function:1-2+3-4+5.....99的所有数之和(结果是50)

start = 0
sum = 0 
sum1 = 0 
sum2 = 0
while True:
    start = start + 1
    if start % 2 ==0:
        sum1 = sum1 - start
    else:
        sum2 = sum2 + start
    sum = sum1 + sum2
    if start == 99:
        break
print(sum)

#!/bin/bash/env python
# -*- coding:utf-8 -*-
#function：给用户三次登录的机会

start = 0
while True:
	start = start + 1
	user = raw_input("Username:")
	pwd = raw_input("Password:")
	if user == "cairui" and pwd == "123":
		print("yes,you can do it.")
		break
	if start == 3:
		break