Is std::vector efficient?

1) std::vector is a sequence container that encapsulates dynamic size arrays. The complexity (efficiency) of common operations on vectors is as follows: Random access – constant 𝓞(1) Insertion or removal of elements at the end – amortized constant 𝓞(1)

Is returning a vector slow?

No. In the best case scenario, RVO (return value optimization) will kick in, which will completely elide any copy/move. In the worst case scenario, the object will be moved out of the function. Moves for std::vector are very cheap (comparable to just a few pointer swaps).

How do I return an STD to a vector?

std::vector f(); That is, return by value. With C++11, std::vector has move-semantics, which means the local vector declared in your function will be moved on return and in some cases even the move can be elided by the compiler.

Are vectors always better than arrays?

Vector is better for frequent insertion and deletion, whereas Arrays are much better suited for frequent access of elements scenario. Vector occupies much more memory in exchange for managing storage and growing dynamically, whereas Arrays are a memory-efficient data structure.

Can you return vectors in C++?

vectors can be returned from a function in C++ using two methods: return by value and return by reference. In this article, we will discuss efficient ways to return a vector from a function in C++.

How do I return two vectors?

No, you cannot return 2 results from a method like in this example. void merge_sort(vector& x, vector& y); Ultimately, you can do what @JoshD mentioned and create a struct called point and merge sort the vector of the point struct instead.

Are vectors more efficient?

1.) Vector will be more efficient if elements are inserted or removed from the back-end only. As, vector internally stores all the elements in consecutive memory location. Therefore, if an element is added in middle, then vector right shifts all the right side elements of that location by 1.