3.初识Python

以下通过Linux命令行模式编写运行Python，粗体表示用户输入信息。

charles@charles:~$python3.5            #  Linux提供的命令行模式

Python 3.5.2 (default, Aug 31 2016, 10:51:09)

[GCC 4.8.4] on linux

Type "help", "copyright", "credits" or "license" for more information.

>>>100+200                         #  Python交互式环境

300

>>>print("hello world")

hello world

>>>exit()

charles@charles:~$vim hello.py

100+200

print("100 + 200 =", 100+200)           # 逗号“,”输出一个空格

print("hello world")

charles@charles:~$python3.5 hello.py

100 + 200 = 300

hello world

charles@charles:~$vim hello_name.py

name = input("Please input your name : ")    #  输入变量

print("hello", name)                                            #  输出变量

charles@charles:~$python3.5 hello_name.py

Please input your name :charles

hello charles

或者

charles@charles:~$vim hello_name.py

#!/usr/local/python/bin/python3.5

name = input("Please input your name : ")

print("hello", name)

charles@charles:~$chmod u+x hello_name.py

charles@charles:~$./hello_name.py

Please input your name :charles

hello charles