What is the difference between const and volatile in C++?

What is the difference between const and volatile in C++?

In C++, const indicates that a variable's value cannot be changed after initialization, while volatile tells the compiler that a variable may be changed by external factors, preventing optimization.

Can you give me an example of when to use volatile?

Sure! Use volatile for variables that can be modified by an interrupt service routine or hardware, like a sensor reading.

What happens if I use const with a pointer?

Using const with a pointer means that the pointer itself can change, but the value it points to cannot be modified. For example, const int* ptr means you can't change the integer value pointed to by ptr.

Are there any performance implications of using volatile?

Yes, using volatile can lead to performance overhead because it prevents certain compiler optimizations, making access to the variable slower.