add Chapter06

Chapter06/function_overloading.cpp

@@ -0,0 +1,17 @@
+#include <cstdio> 
+
+void print(int a) { 
+    printf("Int %d\r\n", a); 
+} 
+
+void print(float a) { 
+    printf("Float %2.f\r\n", a); 
+} 
+
+int main() { 
+
+    print(2); 
+    print(2.f); 
+
+    return 0; 
+}