From a3885719ad2f0d0640200f738f3fca3896eb50b1 Mon Sep 17 00:00:00 2001
From: Lion Chan <cy187lion@sina.com>
Date: Mon, 19 Mar 2018 21:37:23 +0800
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---
 Chapter2 C与C++/2.1 基础语法.md               | 39 +++++++++++++++++++
 ... 类、继承和多态.md => 2.10 C++对C的扩展.md} |  0
 ...ic和const成员.md => 2.11 类、继承和多态.md} |  0
 ...�函数和接口.md => 2.12 static和const成员.md} |  0
 ... 程序的内存结构.md => 2.13 虚函数和接口.md} |  0
 ...加载、运行和关闭.md => 2.14 程序的内存结构.md} |  0
 ...��机题.md => 2.15 程序的加载、运行和关闭.md} |  0
 .../{2.5 数组.md => 2.16 上机题.md}           |  0
 .../{2.6 结构体与联合体.md => 2.5 高级宏操作} |  0
 .../{2.7 高级指针.md => 2.6 数组.md}          |  0
 ...��过程与面向对象.md => 2.7 结构体与联合体.md} |  0
 .../{2.9 C++对C的扩展.md => 2.8 高级指针.md}  |  0
 Chapter2 C与C++/2.9 面向过程与面向对象.md     |  0
 13 files changed, 39 insertions(+)
 rename Chapter2 C与C++/{2.10 类、继承和多态.md => 2.10 C++对C的扩展.md} (100%)
 rename Chapter2 C与C++/{2.11 static和const成员.md => 2.11 类、继承和多态.md} (100%)
 rename Chapter2 C与C++/{2.12 虚函数和接口.md => 2.12 static和const成员.md} (100%)
 rename Chapter2 C与C++/{2.13 程序的内存结构.md => 2.13 虚函数和接口.md} (100%)
 rename Chapter2 C与C++/{2.14 程序的加载、运行和关闭.md => 2.14 程序的内存结构.md} (100%)
 rename Chapter2 C与C++/{2.15 上机题.md => 2.15 程序的加载、运行和关闭.md} (100%)
 rename Chapter2 C与C++/{2.5 数组.md => 2.16 上机题.md} (100%)
 rename Chapter2 C与C++/{2.6 结构体与联合体.md => 2.5 高级宏操作} (100%)
 rename Chapter2 C与C++/{2.7 高级指针.md => 2.6 数组.md} (100%)
 rename Chapter2 C与C++/{2.8 面向过程与面向对象.md => 2.7 结构体与联合体.md} (100%)
 rename Chapter2 C与C++/{2.9 C++对C的扩展.md => 2.8 高级指针.md} (100%)
 create mode 100644 Chapter2 C与C++/2.9 面向过程与面向对象.md

diff --git a/Chapter2 C与C++/2.1 基础语法.md b/Chapter2 C与C++/2.1 基础语法.md
index 20d4a72..86076c6 100644
--- a/Chapter2 C与C++/2.1 基础语法.md	
+++ b/Chapter2 C与C++/2.1 基础语法.md	
@@ -181,11 +181,50 @@ ashort++;
 ```
 
 # 2.1.7 符号常量
+有时候我们希望用一个符号来代替某个字面常量，这看起来很像一个不允许改变值的变量，我们用 const 关键字来修饰它，使之成为符号常量。例如：
+
+```cpp
+const long cnvar0=666;
+const char cnvar1='C';
+```
+
+一个符号常量只能在定义时被初始化，并且不能够被再次赋值。例如下面做法是错的：
+
+```cpp
+const int cnint = 256;
+cnint++;
+```
 
 # 2.1.8 运算符
 
+c语言运算符主要包括赋值运算、算数运算、逻辑运算、位运算、比较运算等。运算符主要涉及到优先级,结合性y以及前加加和后加加的问题。例如：
+
+```cpp
+int val=5, mask=0b0100;
+printf("val=%d.\n", val++);   // val=5.
+printf("val=%d.\n", ++val);   // val=7.
+
+if(val<=10 && val>=5)
+{
+  printf("True\n");
+}
+
+val &= mask;  // val=4.
+```
+
 # 2.1.9 宏
 
+通过使用宏，可以指导c编译器做一些特别的工作。例如使用define关键字来做一些替代的工作：
+```cpp
+#define BASE_ADDR (0x25)
+#define REG1_OFFSET (0x01)
+#define REG2_OFFSET (0x02)
+
+printf("Register 1 addr=0x%x.\n", BASE_ADDR+REG1_OFFSET);
+printf("Register 2 addr=0x%x.\n", BASE_ADDR+REG2_OFFSET);
+```
+这称作宏替换。宏替换可以提高程序的可移植性，例如上述例子中，只要修改 #define BASE_ADDR (0x25) 一处便可以修改所有寄存器的地址。
+
 # 2.1.10 指针
 
 指针变量的长度与总线位宽有关，如32位机则指针变量长度为4，64位机为8。
diff --git a/Chapter2 C与C++/2.10 类、继承和多态.md b/Chapter2 C与C++/2.10 C++对C的扩展.md
similarity index 100%
rename from Chapter2 C与C++/2.10 类、继承和多态.md
rename to Chapter2 C与C++/2.10 C++对C的扩展.md
diff --git a/Chapter2 C与C++/2.11 static和const成员.md b/Chapter2 C与C++/2.11 类、继承和多态.md
similarity index 100%
rename from Chapter2 C与C++/2.11 static和const成员.md
rename to Chapter2 C与C++/2.11 类、继承和多态.md
diff --git a/Chapter2 C与C++/2.12 虚函数和接口.md b/Chapter2 C与C++/2.12 static和const成员.md
similarity index 100%
rename from Chapter2 C与C++/2.12 虚函数和接口.md
rename to Chapter2 C与C++/2.12 static和const成员.md
diff --git a/Chapter2 C与C++/2.13 程序的内存结构.md b/Chapter2 C与C++/2.13 虚函数和接口.md
similarity index 100%
rename from Chapter2 C与C++/2.13 程序的内存结构.md
rename to Chapter2 C与C++/2.13 虚函数和接口.md
diff --git a/Chapter2 C与C++/2.14 程序的加载、运行和关闭.md b/Chapter2 C与C++/2.14 程序的内存结构.md
similarity index 100%
rename from Chapter2 C与C++/2.14 程序的加载、运行和关闭.md
rename to Chapter2 C与C++/2.14 程序的内存结构.md
diff --git a/Chapter2 C与C++/2.15 上机题.md b/Chapter2 C与C++/2.15 程序的加载、运行和关闭.md
similarity index 100%
rename from Chapter2 C与C++/2.15 上机题.md
rename to Chapter2 C与C++/2.15 程序的加载、运行和关闭.md
diff --git a/Chapter2 C与C++/2.5 数组.md b/Chapter2 C与C++/2.16 上机题.md
similarity index 100%
rename from Chapter2 C与C++/2.5 数组.md
rename to Chapter2 C与C++/2.16 上机题.md
diff --git a/Chapter2 C与C++/2.6 结构体与联合体.md b/Chapter2 C与C++/2.5 高级宏操作
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rename to Chapter2 C与C++/2.5 高级宏操作
diff --git a/Chapter2 C与C++/2.7 高级指针.md b/Chapter2 C与C++/2.6 数组.md
similarity index 100%
rename from Chapter2 C与C++/2.7 高级指针.md
rename to Chapter2 C与C++/2.6 数组.md
diff --git a/Chapter2 C与C++/2.8 面向过程与面向对象.md b/Chapter2 C与C++/2.7 结构体与联合体.md
similarity index 100%
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rename to Chapter2 C与C++/2.7 结构体与联合体.md
diff --git a/Chapter2 C与C++/2.9 C++对C的扩展.md b/Chapter2 C与C++/2.8 高级指针.md
similarity index 100%
rename from Chapter2 C与C++/2.9 C++对C的扩展.md
rename to Chapter2 C与C++/2.8 高级指针.md
diff --git a/Chapter2 C与C++/2.9 面向过程与面向对象.md b/Chapter2 C与C++/2.9 面向过程与面向对象.md
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index 0000000..e69de29