编译的概念
把名文代码执行前，先转成二进制，再执行， 这个过程就叫编译
sh test.sh #shell 程序的解释器
编译型与解释型
编译型语言包括：c、c++、go 等
特点：运行效率高 依赖编译平台 linux 操作系统 跟cpu交互的接口，与windows不是完全一样，不能跨平台 ，开发效率低
linux: print_to_console
windows: print_to_screen
解释型语言包括：shell、python、php、ruby 等
特点：运行效率低 跨平台，sh 解释器 负责跟不同的平台沟通，开发效率高，解释型的语言一般不需要关注硬件底层，学习成本低
变量
变量说直白一点就相当于一个容器，用来存储数据到内存中。
变量格式：
驼峰体：TrafficCost = windows 程序开发人员喜欢用 c#
官方推荐：traffic_cost = python
trafficcost age_of_oldboy = 56
ageofoldboy = 56
AGE_OF_OLDBOY = 56 #常量 不变的量
“ctrl + ?” ----> 注释选中的 流程控制
if ... elif ... else 判断
if ...判断条件
elif ...接着上面的继续判断
……
elif ...接着上面的继续判断
else ...上面的条件都不满足，则执行这一条内容
判断xxx的数据类型
print(type(xxx))
4 = integer = int 整数，整型
4 = string = str 字符串
a = string
改变xxx的类型：
int(“xxx”) ---> 转变为整数、整型 （int）
str(xxx) ---> 转变为字符串 （str）
同一类型的数据类型可以 相互操作， 整数+ 整数，
注意：字符串不能与整型进行计算、比较。
实操一
猜年龄 ， 可以让用户最多猜三次
age = 34for i in range(3): age_guess = int(input('input your guess:')) if age_guess > age: print("try smaller...") elif age_guess < age: print("try bigger...") else: print("Congratulations you guessed it") breakelse: print("Input too many times") 或
age = 34count = 0while count<3: age_guess = int(input("input your guess:")) if age_guess > age: print("try smaller...") elif age_guess < age: print("try bigger...") else: print("Congratulations you guessed it") break count += 1else: print("Input too many times") 实操二
猜年龄 ，每隔3次，问他一下，还想不想继续玩，y,n
age = 34count = 0while True: if count < 3: age_guess = int(input("please input your age:")) if age_guess > age: print("try smaller...") elif age_guess < age: print("try bigger...") else : print("Congratulations you guessed it") break count += 1 elif count == 3: select_ge = "Continue to play don't play?(Y/N)" chioce = input("Continue to play don't play?Y/N") if chioce == "y" or chioce == "Y": print("Keep on talking") count = 0 elif chioce == "n" or chioce == "N": print("Do not want to play") break 或
age = 34while True: for i in range( 3 ): age_guess = int(input('input your guess:')) if age_guess > age: print("try smaller...") elif age_guess < age: print("try bigger...") elif age_guess == age: print("Congratulations you guessed it") exit() else : chioce = input("Continue to play don't play?Y/N") if chioce == "y" or chioce == "Y": print("Keep on talking") elif chioce == "n" or chioce == "N": print("Do not want to play") exit() 实操3
编写登陆接口
输入用户名密码认证成功后显示欢迎信息输错三次后锁定