Python 学习第一周

一、pycharm安装

https://www.cnblogs.com/dcpeng/p/9031405.html

二，代码联系

1、输入输出（明文）：

　　username = input("usrname:"）

       password = input("password:"）

　　print(username,password)

2、输入输出（暗文）：

import getpass ##输入的时候没有显示输入字符

 username = input("usrname:")

password = getpass.getpass("password:")
print(username,password)

3、验证输入的账号密码是否正确：

_username = 'alex'
_password = 'abc123'
username = input("username")
password = input('password:')
if _username == username and _password ==password:
    print("Welcome user {name} login...".format(name=username))
else:
    print("Invalid username or password!")

 4、猜年龄 if else 

age_of_oldboy = 56
guess_age = int(input("guess age:"))###输入必须为整数，不让报错
if guess_age == age_of_oldboy:
    print("yes,you got it.")
elif guess_age > age_of_oldboy:
    print("think smaller....")
else:
    print("think bigger!")

5、while循环

count = 0
while True:
    print("count:",count)
    count = count+1
    if count ==100:
        break
输出0-99 

count = 0
while True:
    if count ==3:
        break
    guess_age = int(input("guess age:"))

    if guess_age == age_of_oldboy:
            print("yes,you got it.")
            break
    elif guess_age > age_of_oldboy:
            print("think smaller....")
    else:
            print("think bigger!")
    count+=1

6、优化后

age_of_oldboy = 56
count = 0
while count<3:
    guess_age = int(input("guess age:"))
    if guess_age == age_of_oldboy:
            print("yes,you got it.")
            break
    elif guess_age > age_of_oldboy:
            print("think smaller....")
    else:
            print("think bigger!")
    count+=1

7、for 循环

for i in range(10):
    print("loop",i)

for i in range(3):
    guess_age = int(input("guess age:"))
    if guess_age == age_of_oldboy:
            print("yes,you got it.")
            break
    elif guess_age > age_of_oldboy:
            print("think smaller....")
    else:
            print("think bigger!")
else:
    print("you have tried too many times ..")

8、有间隔的for循环 

for i in range(0,10,3):##隔三个数
    print("loop",i)

输出结果

loop 0
loop 3
loop 6
loop 9

9、用户控制

age_of_oldboy = 56
count = 0
while count<3:
    guess_age = int(input("guess age:"))
    if guess_age == age_of_oldboy:
            print("yes,you got it.")
            break
    elif guess_age > age_of_oldboy:
            print("think smaller....")
    else:
            print("think bigger!")
    count+=1

    if count==3:####重点
        continue_confirm = input("do you want to keep guessing?")
        if continue_confirm !='n':
            count =0
10、双层循环

for i in range(10):
    print('--------',i)
    for j in range(10):
        print(j)
        if j>5:
            break