From c0d76f164df850f96a24351a6e00b8fa580a2429 Mon Sep 17 00:00:00 2001
From: CYP12138 <1375405618@qq.com>
Date: Wed, 16 Mar 2022 18:05:59 +0800
Subject: [PATCH] =?UTF-8?q?=E7=BC=96=E8=AF=91=E5=99=A8=E4=BC=98=E5=8C=96si?=
 =?UTF-8?q?zeof,private=E7=BB=A7=E6=89=BF=E8=AE=BF=E9=97=AE=E6=9D=83?=
 =?UTF-8?q?=E9=99=90=E6=9B=B4=E6=94=B9?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 basic_content/sizeof/README.md                | 21 +++++++++---
 basic_content/sizeof/geninhe.cpp              | 14 ++++++--
 .../day5/继承访问权限/readme.md               | 32 ++++++++++++++++---
 3 files changed, 57 insertions(+), 10 deletions(-)

diff --git a/basic_content/sizeof/README.md b/basic_content/sizeof/README.md
index 7cfdbc0..4fd0e12 100644
--- a/basic_content/sizeof/README.md
+++ b/basic_content/sizeof/README.md
@@ -93,7 +93,7 @@ int main()
 /**
  * @file geninhe.cpp
  * @brief 1.普通单继承,继承就是基类+派生类自身的大小(注意字节对齐)
- * 注意：类的数据成员按其声明顺序加入内存，与访问权限无关，只看声明顺序。
+ * 注意：类的数据成员按其声明顺序加入内存，无访问权限无关，只看声明顺序。
  * 2.虚单继承，派生类继承基类vptr
  * @author 光城
  * @version v1
@@ -117,7 +117,14 @@ class A
  * int b
  * short a
  * long b
- * 根据字节对齐4+4=8+8+8=24
+ * 根据字节对齐4+4+8+8=24
+ * 
+ * 或编译器优化
+ * char a
+ * short a
+ * int b
+ * long b
+ * 根据字节对齐2+2+4+8=16
  */
 class B:A
 {
@@ -125,24 +132,30 @@ class B:A
         short a;
         long b;
 };
+/**
+* 把A的成员拆开看，char为1，int为4，所以是1+（3）+4+1+（3）=12，（）为字节补齐
+*/
 class C
 {
     A a;
     char c;
 };
+
 class A1
 {
     virtual void fun(){}
 };
-class C1:public A1
+class C1:public A
 {
 };
 
+
 int main()
 {
     cout<<sizeof(A)<<endl; // 8
-    cout<<sizeof(B)<<endl; // 24
+    cout<<sizeof(B)<<endl; // 16 或 24
     cout<<sizeof(C)<<endl; // 12
+
     /**
      * @brief 对于虚单函数继承，派生类也继承了基类的vptr，所以是8字节
      */
diff --git a/basic_content/sizeof/geninhe.cpp b/basic_content/sizeof/geninhe.cpp
index a0acaad..39cf4b4 100644
--- a/basic_content/sizeof/geninhe.cpp
+++ b/basic_content/sizeof/geninhe.cpp
@@ -25,7 +25,14 @@ class A
  * int b
  * short a
  * long b
- * 根据字节对齐4+4=8+8+8=24
+ * 根据字节对齐4+4+8+8=24
+ *
+ * 或编译器优化
+ * char a
+ * short a
+ * int b
+ * long b
+ * 根据字节对齐2+2+4+8=16
  */
 class B:A
 {
@@ -33,6 +40,9 @@ class B:A
         short a;
         long b;
 };
+/**
+* 把A的成员拆开看，char为1，int为4，所以是1+（3）+4+1+（3）=12，（）为字节补齐
+*/
 class C
 {
     A a;
@@ -51,7 +61,7 @@ class C1:public A
 int main()
 {
     cout<<sizeof(A)<<endl; // 8
-    cout<<sizeof(B)<<endl; // 24
+    cout<<sizeof(B)<<endl; // 16
     cout<<sizeof(C)<<endl; // 12
 
     /**
diff --git a/practical_exercises/10_day_practice/day5/继承访问权限/readme.md b/practical_exercises/10_day_practice/day5/继承访问权限/readme.md
index 3face3a..5a8463b 100644
--- a/practical_exercises/10_day_practice/day5/继承访问权限/readme.md
+++ b/practical_exercises/10_day_practice/day5/继承访问权限/readme.md
@@ -1,14 +1,30 @@
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