How do I reserve capacity and shrink-to-fit with std::unordered_set?

In C++, the std::unordered_set is a container that provides unique elements in an unordered fashion. To manage performance effectively, it is often helpful to reserve capacity beforehand and shrink the capacity when it's no longer needed. This article demonstrates how to use the reserve and shrink_to_fit methods with std::unordered_set.

Keywords: std::unordered_set, C++, reserve, shrink_to_fit, container management
Description: Learn how to effectively manage capacity in std::unordered_set by reserving space and shrinking it to fit the current number of elements.
#include <iostream> #include <unordered_set> int main() { // Creating an unordered set std::unordered_set my_set; // Reserving capacity for 10 elements my_set.reserve(10); // Inserting elements for (int i = 1; i <= 10; ++i) { my_set.insert(i); } std::cout << "Size before shrink_to_fit: " << my_set.size() << std::endl; // Shrinking to fit the current size my_set.max_load_factor(1.0); // Reset load factor if needed my_set.rehash(my_set.size()); // Rehashing to shrink std::cout << "Size after shrink_to_fit: " << my_set.size() << std::endl; return 0; }

Keywords: std::unordered_set C++ reserve shrink_to_fit container management

Related Questions

How do I avoid rehashing overhead with std::set in multithreaded code?

How do I find elements with custom comparators with std::set for embedded targets?

How do I erase elements while iterating with std::set for embedded targets?

How do I provide stable iteration order with std::unordered_map for large datasets?

How do I reserve capacity ahead of time with std::unordered_map for large datasets?

How do I erase elements while iterating with std::unordered_map in multithreaded code?

How do I provide stable iteration order with std::map for embedded targets?

How do I provide stable iteration order with std::map in multithreaded code?

How do I avoid rehashing overhead with std::map in performance-sensitive code?

How do I merge two containers efficiently with std::map for embedded targets?