How to Efficiently Assign a std::vector from a C-Style Array?

Assigning a std::vector from a C-Style Array Efficiently

When working with data restrictions, it can be challenging to integrate C-style arrays with modern C constructs like std::vector. This question delves into the efficient assignment of a std::vector using a C-style array.

The class Foo, as described in the question, faces the dilemma of receiving data as a C-style array but needing to store it within a std::vector. Straightforward approaches involving resizing and looping or utilizing std::copy() are viable, but further optimization may be desirable.

The secret lies in recognizing the power of pointer-to-iterator conversion. Consider the following snippet:

w_.assign(w, w + len);

In this code, the pointers w and w len define the beginning and end of the C-style array, respectively. When passed to the assign() method, this range is interpreted as an iterator range, allowing std::vector to efficiently initialize itself from the array.

This method leverages C 's underlying type system to seamlessly convert pointers to iterators, providing the most concise and efficient solution for assigning a std::vector from a C-style array.

The above is the detailed content of How to Efficiently Assign a std::vector from a C-Style Array?. For more information, please follow other related articles on the PHP Chinese website!