Can You Modify Elements Directly in an STL Set?

Modifying Elements in Standard Template Library (STL) Sets

Manipulating values stored in an STL set directly is generally discouraged. When modifying an element through an iterator, it remains in the set but its position may become incorrect. The documentation from Microsoft Developer Network (MSDN) emphasizes:

"The value of an element in a set may not be changed directly. Instead, you must delete old values and insert elements with new values."

This restriction arises from the underlying implementation of sets, often as red-black trees. If the value is modified without notifying the set, it can lead to inconsistencies in the tree structure. For instance, the element's position within the tree will be incorrect, resulting in inaccurate searches and possibly undefined behavior.

Therefore, to avoid unpredictable outcomes, it is recommended to remove the old element and insert a new one with the desired value when modifying elements in an STL set.

The above is the detailed content of Can You Modify Elements Directly in an STL Set?. For more information, please follow other related articles on the PHP Chinese website!