How does std::vector perform in C++?

How does std::vector perform in C++ compared to other containers?

std::vector is generally very efficient for dynamic arrays, offering fast access and good memory locality. However, it can be slower than other containers like std::list for certain operations like insertions and deletions.

What are the time complexities for common operations in std::vector?

The time complexities are as follows: Access is O(1), Insertion at the end is amortized O(1), Insertion at the beginning or middle is O(n), and Deletion is O(n).

Are there any performance pitfalls I should be aware of when using std::vector?

Yes, one common pitfall is excessive reallocations when the vector grows. It's often better to reserve space in advance if you know the size.

How does std::vector handle memory allocation?

std::vector manages memory automatically. It allocates more memory than needed to accommodate growth, which helps reduce the number of reallocations.