How to Safely Remove Elements from a std::vector While Iterating?

Efficaciously Removing Elements from std::vector While Iterating

In the realm of C programming, developers often encounter the challenge of manipulating a std::vector while traversing its elements. While iterators provide a convenient mechanism for this task, a common pitfall arises when attempting to remove elements during iteration.

Consider the scenario where a std::vector is used to store a list of paths to files. The goal is to delete each file and remove its path from the vector. However, using traditional methods, such as the erase() method, invalidates iterators after each deletion, complicating further traversal.

To overcome this limitation, developers have devised a more efficient approach. The erase() method, when invoked, not only removes the designated element but also returns a new iterator pointing to the next element. This unique behavior allows for a smooth continuation of the loop:

<code class="cpp">std::vector<std::string>::iterator iter;
for (iter = m_vPaths.begin(); iter != m_vPaths.end(); ) {
    if (::DeleteFile(iter->c_str()))
        iter = m_vPaths.erase(iter);
    else
        ++iter;
}</code>

In this code snippet, the loop continues as intended, with iter being automatically updated to point to the next valid element after each deletion. This efficient method eliminates the need for an additional vector and streamlines the process of removing elements while iterating.

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