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

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

In C++, 'const' means that the value cannot be changed, while 'const reference' allows you to refer to a constant value without copying it.

Can you give me an example of using const and const reference?

Sure! Here's an example:

void func(const int x) {
    // x cannot be modified here
}

void funcRef(const int& y) {
    // y cannot be modified, but it's a reference to the original variable
}

Why would I use const reference instead of just const?

Using const reference is more efficient for large objects because it avoids copying the object, while still preventing modification.

Are there any downsides to using const references?

One downside is that if the original object goes out of scope, the reference becomes invalid, leading to potential undefined behavior.