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Hi,for this part, I will record the learning pace of myself about the following programming language.

Content

• C++
• Java
• Python
• R
• SQL

Overview

This page I will also write down some basic knowledge about the algo

• Curly Braces {} 大括号
• Parentheses () 小括号（圆括号）
• Square Brackets [] 中括号
• Angle Brackets <> 尖括号

1. java

• (从.java到.class):javac HelloWorld.java
• java -cp .. HW1.HelloWorld args[0] args[1]

  HW1 为上层目录

2. C++:

• gcc helloWorld.c

（1） 在C++中，我们经常在开始写代码之前加入：
using namespace std;
后续就可以只写：
cout << “This” << endl

（2） when to add Comma

behind the non-control statement

• control statement: if;while;switch;break;for——alter the program’s flow

• non-control statement: variable declaration,assignment,function call——perform operation without affecting the flows

(3) forward declarations

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void function2(int a, string b);
int function(int a, string b) {
function2(a, b); // now you can call this before writing
	return a + 2;    // function2
}
void function2(int a, string b) {
	cout << b << a + 2 << endl;
}

3.Python

4.Java

5.SQL