The document discusses reference variables and how objects stored in data structures by reference can cause issues if the objects are transient. It provides an example where objects created on the stack disappear after the function returns. To prevent this, the document recommends allocating objects on the heap using new, so the objects persist in memory even after the function returns. It also discusses using delete to remove objects from the heap when no longer needed.

1. Class No.18 Data Structures http://ecomputernotes.com

6. Memory Organization Code Static data Stack Heap Process 1 (browser) Process 3 (word) Process 4 (ourtest.exe) Windows OS Process 2 (dev-c++) http://ecomputernotes.com

7. Reference Variables Call stack layout when q.enqueue(c2) called in loadCustomer. 1052 1060 1068 1056 600 1072 624 . . . c1 c2 loadCustomer enqueue stack grows downwards sp (elt) (624) elt

8. Reference Variables Heap layout during call to loadCustomer. 600 624 c1 c2 Customer(“irfan”) -> c1 heap grows upwards 648 Customer(“sohail”) -> c2 irfan sohail http://ecomputernotes.com