python第一讲练习题

第一题答案：

<span style="font-family:FangSong_GB2312;font-size:18px;">#!/usr/bin/env python
# -*- coding:utf-8 -*-
#思路：
#a.先写出1-10
#b.在排除7
num1 = 1
while True :
if num1 == 7 :
num1 += 1
continue
print(num1)
if num1 == 10 :
break

num1 += 1</span>

<span style="font-family:FangSong_GB2312;font-size:18px;">!/usr/bin/env python
# -*- coding:utf-8 -*-
num1 = 1
for i in range(1,11):
if i == 7:
continue
print(i)</span>

<span style="font-family:FangSong_GB2312;font-size:18px;">#!/usr/bin/env python
# -*- coding:utf-8 -*-
num = 1
he = 0
while True :
he += num
 print(he)
if num == 100:
break
num += 1</span>

<span style="font-family:FangSong_GB2312;font-size:18px;">#!/usr/bin/env python
# -*- coding:utf-8 -*-
he = 0
for i in range(1,101):
he += i
print(he)</span>

<span style="font-family:FangSong_GB2312;font-size:18px;">#!/usr/bin/env python
# -*- coding:utf-8 -*-

#输出1-100内的所有奇数
#思路：
#先输出1-100 所有的数字
#在排除偶数   奇数除以2都余1

input_num = 1

while True:

if input_num % 2 == 1:
print(input_num)

if input_num == 100:
break

input_num += 1</span>

<span style="font-family:FangSong_GB2312;font-size:18px;">#!/usr/bin/env python
# -*- coding:utf-8 -*-

for i in range(1,101):
if i % 2 == 0:
print(i)</span>

#!/usr/bin/env python
# -*- coding:utf-8 -*-

#思路：
#a.先列出来1-100的数
#b.判断如何数是奇数，那么减掉后边的偶数
#c.同理，在判断偶数
#&&&注意算法：容易混
he = 0
num1 = 1
while True:
if num1 % 2 == 1:
he = he + num1   #这里容易想成减法
#	print("please",he)
elif num1 % 2 == 0:
he = he - num1  #这里容易想成加法
#	print("please",he)
print(he)   #这个显示的位置也容易放错
if num1 == 99:
break
elif num1 > 99:
break

#   print(num1)
num1 += 1

<span style="font-family:FangSong_GB2312;font-size:18px;">#!/usr/bin/env python
# -*- coding:utf-8 -*-
#思路：
#a.先写出输入用户名跟密码，完成流程
#b.在完成输入3次后不管对错都结束

a = 1

import getpass

while a < 3 :
name1 = input("please input you name :  ")
passwd = getpass.getpass("please input you password : ")
print(name1)
print(passwd)

if name1 == "alex" and passwd == "123":
break
else:
print("try again")
 a += 1</span>

<span style="font-family:FangSong_GB2312;font-size:18px;">#!/usr/bin/env python
# -*- coding:utf-8 -*-
a = 1
coount = True
import getpass

while coount :
name1 = input("please input you name :  ")
passwd = getpass.getpass("please input you password : ")

if a == 3 or coount == False:
break
elif a >3:
break
else:
print(name1)
print(passwd)
a += 1
</span>

<span style="font-family:FangSong_GB2312;font-size:18px;">#!/usr/bin/env python
# -*- coding:utf-8 -*-
import getpass

for i in range(1,4):
usernam_e = input("please input you name:")
passw_d = getpass.getpass("please input you password :")
print(usernam_e)
print(passw_d)
print("you input for :",i)
if i == 3:
print("you have input 0 chance")

##问题：getpass无法完成输入过程，给成input就可以？？？？
##问题答案：是win的问题</span>