diff --git a/ChangeLog b/ChangeLog
index f3a8770..72ac561 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,21 @@
+2024-10-29  Mert Gör  <mertgor@masscollabs.xyz>
+
+	* c-basic/hex.c: Experımental Branch page 21
+
+	#include <stdio.h>
+
+	int main()
+	{
+		int a, b;
+
+		printf("Enter a number: \n");
+		scanf("%x", &a);
+		printf("a = %d\n", a);
+
+		return 0;
+	}	
+
+
 2024-10-23  Mert Gör  <hwpplayer1@debian>
 
 	*  (cc1): Tüm dersler incelendi. Pratiğe dökülecek konular : GNU Emacs, Linux kernel, Assembly(80X86 ve arm)
diff --git a/c-basic/hex.c b/c-basic/hex.c
new file mode 100644
index 0000000..e9a42d9
--- /dev/null
+++ b/c-basic/hex.c
@@ -0,0 +1,12 @@
+#include <stdio.h>
+
+int main()
+{
+  int a, b;
+
+  printf("Enter a number: \n");
+  scanf("%x", &a);
+  printf("a = %d\n", a);
+
+  return 0;
+}
diff --git a/c-basic/scanf.c b/c-basic/scanf.c
new file mode 100644
index 0000000..56f3286
--- /dev/null
+++ b/c-basic/scanf.c
@@ -0,0 +1,10 @@
+#include <stdio.h>
+
+int main()
+{
+  int a;
+
+  printf("enter a number : \n");
+  scanf("%d,", &a);
+  printf("your number is : %d\n", a);
+}
diff --git a/c-basic/scanf_ab.c b/c-basic/scanf_ab.c
new file mode 100644
index 0000000..09af5e7
--- /dev/null
+++ b/c-basic/scanf_ab.c
@@ -0,0 +1,14 @@
+#include <stdio.h>
+
+int main()
+{
+  int a, b;
+
+  printf("enter 'a' number : \n");
+  scanf("%d,", &a);
+  printf("enter 'b' number : \n");
+  scanf("%d, ", &b);
+  printf("your numbers a = %d , b = %d\n", a, b);
+
+  return 0;
+}