Oral Exam - memory, references, and parameters - mini

Describe pass by value

Copies argument → safe but slower for large data

Describe pass by reference

Passes address → faster, can modify original variable.

Compare pass by value/reference

Value = copy, safe; Reference = efficient, modifiable.

Describe pointers

Store memory addresses; referenced with *.

Describe references

Alternate names for existing variables; must be initialized.

Compare pointers and references 

Pointers can be null/reassigned; references can’t.

How are pointers different from variables

Store addresses, not actual values

Why prefer pass-by-reference

 Efficiency and ability to modify arguments

Advantages/disadvantages of pass by value/pass by reference

By value: safe but slow; By reference: efficient but risk unintended modification

Describe garbage collection

Automatic memory cleanup (not in C++).

C++ has no garbage collection - implication?

Programmers must manage new/delete manually

Describe memory leaks

Allocated memory not freed; causes lost resources.

Describe memory fragmentation

Freeing blocks creates gaps, reducing usable continuous memory.

Describe paging/sweeping

 Moving data between RAM and disk to manage limited memory.

Dynamic allocation/freeing memory

arrays use new[], delete[]

Describe scope

Defines variable visibility; inner scope hides outer

Name conflict across scopes

 Inner takes precedence; access outer via ::.

Describe default parameters

Placed at the end of the parameter list; supply defaults for missing args.

What does a function’s type mean?

Its return type — what kind of value it outputs