add const

01.Basic/Constant.cpp

+#include <iostream>
+using namespace std;
+
+#define LENGTH 10   
+#define WIDTH  5
+#define NEWLINE '\n'
+
+int main()
+{
+
+   int area;  
+   
+   area = LENGTH * WIDTH;
+   cout << area << " | defined by #define";
+   cout << NEWLINE;
+   // return 0;
+
+   const int  CONS_LENGTH = 7;
+   const int  CONS_WIDTH  = 8;
+   const char CONS_NEWLINE = '\n';
+   // int area;  
+
+   area = CONS_LENGTH * CONS_WIDTH;
+   cout << area << " | defined by const";
+   cout << NEWLINE;
+   return 0;
+
+}
\ No newline at end of file