2017 資訊營

Programming basics

A "Program" ?

If you think programming is

Assembly language

So we have

High level language !

You can use human-readable code

And turn it into machine code

Then run it

Let's get started!

Linux

Windows

Not free
closed source
often being attacked by virus
GUI friendly
for general use (slides/documents/games)

Linux

Free
open source
resist most virus designed for windows
CLI friendly
for development use (compilers/editors/...)

WannaCry ?

Linux command

指令	用途	用法
cd	進入目錄(資料夾)	cd <directory>
ls	顯示目錄中檔案	ls [-la]
rm	刪除檔案	rm <file>
mkdir	建立目錄	mkdir <dir name>
g++	編譯C++原始碼	g++ <file name>
./<program name>	執行程式	./<program name>
vim	文字編輯器	見下頁

vim command

指令	用途	用法
i	進入輸入模式	i
ESC	回到指令模式	ESC
:w	存檔	:wq 存檔並離開
:q	離開	:q! 不存檔就離開
vim <filename>	開啟檔案用vim編輯

PRACTICE MODE

Try it !

 // use C++ standard library
#include <iostream>

using namespace std;

// each program must have main function
int main()
{
    cout << "Hello World!" << endl;
    //use "cout" to output text to screen
    return 0;
}

Run it !

Input data

#include <iostream>

using namespace std;

int main(int argc, char *argv[])
{
    int number;
    cout << "Please input a number:";
    cin >> number;
    cout << "yout input is " << number << endl;

    return 0;
}

Multiple input

#include <iostream>

using namespace std;

int main(int argc, char *argv[])
{
    int number1, number2;
    cout << "Please input 2 number:";
    cin >> number1 >> number2;
    cout << "number1 is " << number1 << endl;
    cout << "number2 is " << number2 << endl;

    return 0;
}