Counting allocations through layered resources

Tracing memory allocation and resource management in C++

This is a hard code-tracing question that tests your ability to mentally execute a C++ program involving layered resource allocation and destruction. It rewards precise understanding of object lifetime, constructor and destructor sequencing, and how temporary objects are handled across nested scopes.

To solve this, you need to track the order in which objects are constructed and destroyed, pay close attention to when temporaries are materialized and when they fall out of scope, and understand how resource acquisition and release interact across different layers of the program. The output depends critically on getting the sequence right—off-by-one mistakes in the trace are common.

• Constructor and destructor call order
• Scope and lifetime of local and temporary objects
• Resource acquisition and release semantics
• Expression evaluation order in C++