diff --git a/7-pointers-arrays/CMakeLists.txt b/7-pointers-arrays/CMakeLists.txt
index 191739e..e72df11 100644
--- a/7-pointers-arrays/CMakeLists.txt
+++ b/7-pointers-arrays/CMakeLists.txt
@@ -1,3 +1,4 @@
+add_executable(memory memory.c)
 add_executable(pointer pointer.c)
 add_executable(selection-sort-pointers selection-sort.c)
 add_executable(pointer-array pointer-array.c)
diff --git a/7-pointers-arrays/memory.c b/7-pointers-arrays/memory.c
new file mode 100644
index 0000000..0e221e0
--- /dev/null
+++ b/7-pointers-arrays/memory.c
@@ -0,0 +1,12 @@
+// Created by hfwei on 2024/11/15.
+
+#include <stdio.h>
+
+int main(void) {
+  int i = 50;
+
+  scanf("%d", &i);
+  printf("%d\n", i);
+
+  return 0;
+}
\ No newline at end of file
diff --git a/7-pointers-arrays/pointer.c b/7-pointers-arrays/pointer.c
index 352be7b..4894fcd 100644
--- a/7-pointers-arrays/pointer.c
+++ b/7-pointers-arrays/pointer.c
@@ -36,8 +36,6 @@ int main(void) {
   int *ptr_radius_2 = &radius_2;
 
   ptr_radius_1 = ptr_radius_2;
-  *ptr_radius_2 = 2000;
-  printf("radius_1 = %d\n", *ptr_radius_1);
   /********** On ptr_radius_1 as lvalue and rvalue **********/
 
   /********** On *ptr_radius_1 **********/
@@ -45,14 +43,29 @@ int main(void) {
   // *ptr_radius_1 behaves like radius_1
   *ptr_radius_1 = 200;
   printf("radius_1 = %d\n", radius_1);
+
   circumference = 2 * PI * (*ptr_radius_1);
   /********** On *ptr_radius_1 **********/
 
+  /********** On types of pointers **********/
+  int i = -1;
+
+  unsigned int *ptr_i_double = &i;
+  printf("i = %u\n", *ptr_i_double);
+
+  unsigned int hex = 0x44434241;
+  char *ptr_hex = &hex;
+  printf("i = %c\n", *ptr_hex);
+  printf("i = %c\n", *(ptr_hex + 1));
+  /********** On types of pointers **********/
+
+  /********** On types of pointers (more) **********/
   int v = 100;
   int *pv = &v;
   printf("pv : %p\n *pv : %d\n", pv, *pv);
   pv = &pv;
   printf("pv : %p\n", pv);
+  /********** On types of pointers (more) **********/
 
   return 0;
 }
\ No newline at end of file
diff --git a/pdf/7-pointers-arrays.pdf b/pdf/7-pointers-arrays.pdf
index 81b6312..aa548a7 100644
Binary files a/pdf/7-pointers-arrays.pdf and b/pdf/7-pointers-arrays.pdf differ
diff --git a/template/7-pointers-arrays/7-pointer-array-template.pdf b/template/7-pointers-arrays/7-pointer-array-template.pdf
new file mode 100644
index 0000000..7cf391c
Binary files /dev/null and b/template/7-pointers-arrays/7-pointer-array-template.pdf differ
diff --git a/template/7-pointers-arrays/memory.c b/template/7-pointers-arrays/memory.c
new file mode 100644
index 0000000..0e221e0
--- /dev/null
+++ b/template/7-pointers-arrays/memory.c
@@ -0,0 +1,12 @@
+// Created by hfwei on 2024/11/15.
+
+#include <stdio.h>
+
+int main(void) {
+  int i = 50;
+
+  scanf("%d", &i);
+  printf("%d\n", i);
+
+  return 0;
+}
\ No newline at end of file
diff --git a/template/7-pointers-arrays/pointer.c b/template/7-pointers-arrays/pointer.c
index 804e6af..acee6c6 100644
--- a/template/7-pointers-arrays/pointer.c
+++ b/template/7-pointers-arrays/pointer.c
@@ -10,14 +10,14 @@ int main(void) {
   // https://intellij-support.jetbrains.com/hc/en-us/community/posts/115000740490-Where-did-the-black-windows-go-?page=1#community_comment_115000619510
   //  setbuf(stdout, NULL);
 
-  /********** On radius_1 **********/
+  /********** On radius_1 as lvalue and rvalue **********/
   int radius_1 = 100;
 
   printf("radius_1 = %d\n", radius_1);
 
   double circumference = 2 * PI * radius_1;
   printf("circumference = %f\n", circumference);
-  /********** On radius_1 **********/
+  /********** On radius_1 as lvalue and rvalue **********/
 
   /********** On ptr_radius_1 **********/
   /********** On ptr_radius_1 **********/
@@ -28,5 +28,11 @@ int main(void) {
   /********** On *ptr_radius_1 **********/
   /********** On *ptr_radius_1 **********/
 
+  /********** On types of pointers **********/
+  /********** On types of pointers **********/
+
+  /********** On types of pointers (more) **********/
+  /********** On types of pointers (more) **********/
+
   return 0;
 }
\ No newline at end of file