Python自学之路 ---- day 1

通过第一天的学习我知道了Python是一个解释性，动态的强类型语言。

注释方式

1.单行注释

1 # xxx

2.多行注释

'''
xxx

'''

3.开头注释

1 #!/usr/bin/env python     #在指定文件夹下搜索python解释器，如果没有然后在全盘搜索
2 # -*- coding:utf-8 -*-    #编码集
3 # Author:LQC              #声名作者

4.字符编码发展史

最基本的定义变量的方法

1 name = "LQC"
2 
3 print("My name is",name)

输出

1 My name is LQC

在Python中没有强制性规定常量的表示方法，所以我们大写变量名来规定成为常量，并不是说大写变量名里面的数值不可以更改，指是一种命名习惯

1 NAME  = “LQC” #可以理解为常量LQC

例如

1 name = "LQC"
2 name2 = name
3 print("My name is",name,name2)

输出

My name is LQC LQC

再赋给name一个新的值

1 name = "LQC"
2 name2 = name
3 #print("My name is",name,name2)
4 name = "Loki"
5 print("My name is",name,name2)

输出

My name is Loki LQC

why？

Because name2通过之前的变量name找到了其里面的数值“LQC”，所以name2里面的数值相应的就变成了“LQC”，之后name里面的数值发生了变化，可是name2已经有了数值，所以不随name的赋值随时而改变。可以这么理解name2 = name 是通过先找到name，之后在读取他里面的值赋给自己，而不是一直随着name所赋值的改变而持续改变。

命名规范

变量名应该让其他人都能大致读懂你的意思，都用英文单词来表示

1 name = "LQC"  #✓
2 
3 xingming = "LQC"  #low
4  
5 姓名 = "LQC"   #low

如果想表示的变量名过长怎么办？（LQC's girlfriend）

1.官方推荐使用格式

1 gf_of_LQC = "Sun jia"

2.每一个单词的首字母大写

1 GfOfLqc = "Sun jia"

用户输入信息在输出

1 name = input("name:")
2 age = int(input("age:")) #把输入的数值类型"str"强制传换成"int"
3 print(type(age)) #打印数据类型
4 job = input("job:")
5 salary = input("salary:")
6 print(name,age,job,salary)

输出

name:LQC
age:22
<class 'int'>
job:student
salary:1500
LQC 22 student 1500

规定一个格式，进行格式化输出

------------ info of LQC ------------
name:LQC
age:21
job:student
salary:1500

Method 1

 1 name = input("name:")
 2 age = int(input("age:")) #把输入的数值类型"str"强制传换成"int"
 3 print(type(age)) #打印数据类型
 4 job = input("job:")
 5 salary = input("salary:")
 6 
 7 info = '''
 8 ------------ info of %s -----------
 9 name:%s
10 age:%d
11 job:%s
12 salary:%s
13 ''' % (name,name,age,job,salary)
14 
15 print(info)

View Code

Method 2

 1 name = input("name:")
 2 age = int(input("age:")) #把输入的数值类型"str"强制传换成"int"
 3 print(type(age)) #打印数据类型
 4 job = input("job:")
 5 salary = input("salary:")
 6 
 7 info2 = '''
 8 ------------ info of {_name} -----------
 9 name:{_name}
10 age:{_age}
11 job:{_job}
12 salary:{_salary}
13 '''.format(_name = name,
14            _age = age,
15            _job = job,
16            _salary = salary)
17 
18 print(info2)

View Code

Method 3

 1 name = input("name:")
 2 age = int(input("age:")) #把输入的数值类型"str"强制传换成"int"
 3 print(type(age)) #打印数据类型
 4 job = input("job:")
 5 salary = input("salary:")
 6 
 7 info3 = '''
 8 ------------ info of {0} -----------
 9 name:{0}
10 age:{1}
11 job:{2}
12 salary:{3}
13 '''.format(name,age,job,salary)
14 
15 print(info3)

View Code

while循环

1 count = 0
2 while True :
3     print("count:",count)
4     count = count + 1 #count + =1
5     if count == 1000:
6         break

输出

count: 0
count: 1
count: 2
count: 3
.
.
.
count: 997
count: 998
count: 999

View Code

Break是结束整个循环

Continue是跳出本次循环执行下一次循环

for循环

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

输出

loop 0
loop 1
loop 2
loop 3
loop 4
loop 5
loop 6
loop 7
loop 8
loop 9

View Code

for控制步长

1 for i in range(0,10,2):
2     print("loop", i)

输出

loop 0
loop 2
loop 4
loop 6
loop 8

View Code

循环套循环

1 for i in range(10):
2     print("------------",i)
3     for j in range(10):
4         print(j)
5         if j > 5:
6             break

输出

------------ 0
0
1
2
3
4
5
6
------------ 1
0
1
2
3
4
5
6
.
.
.

View Code

小游戏：猜年龄

While Methon

 1 age_of_LQC = 21
 2 count = 0
 3 while count <3:
 4      guess_age = int(input("age:"))
 5      if age_of_LQC == guess_age:
 6         print("yes, you got it !")
 7         break
 8      elif age_of_LQC > guess_age:
 9         print("think bigger...")
10      else :
11         print("think smaller...")
12      count = count + 1
13      if count == 3:
14          countine_confirm = input("do you want to keep guessing..?")
15          if countine_confirm != 'n':
16              count = 0

View Code

For Methon

 1 age_of_LQC = 21
 2 
 3 for i in range(3):
 4      guess_age = int(input("age:"))
 5      if age_of_LQC == guess_age:
 6         print("yes, you got it !")
 7         break
 8      elif age_of_LQC > guess_age:
 9         print("think bigger...")
10      else :
11         print("think smaller...")
12 
13 else :
14     print("you have tried too many times... fuck off")

View Code

posted on 2018-02-01 15:09 LokiPrime 阅读(262) 评论(0) 收藏举报