How do I use allocator-aware containers in C++?

In C++, allocator-aware containers are part of the Standard Template Library (STL) and allow for custom memory management and object allocation strategies. These containers, such as std::vector, std::list, and std::map, can utilize user-defined allocators. This feature is particularly useful in scenarios where memory allocation needs to be optimized for performance or specific use cases.

Using Allocator-Aware Containers

To use allocator-aware containers, you simply need to define your allocator and then specify it as a template argument when declaring the container. Here is a basic example of using a custom allocator with std::vector.


        #include <iostream>
        #include <vector>
        #include <memory>

        template<typename T>
        class MyAllocator {
        public:
            using value_type = T;

            MyAllocator() = default;

            template<typename U>
            MyAllocator(const MyAllocator<U>&) {}

            T* allocate(std::size_t n) {
                std::cout << "Allocating " << n << " element(s)." << std::endl;
                return static_cast<T*>(::operator new(n * sizeof(T)));
            }

            void deallocate(T* p, std::size_t) {
                std::cout << "Deallocating memory." << std::endl;
                ::operator delete(p);
            }
        };

        int main() {
            std::vector<int, MyAllocator<int>> vec;
            vec.push_back(1);
            vec.push_back(2);
            vec.push_back(3);

            for (const auto &val : vec) {
                std::cout << val << " ";
            }

            return 0;
        }

How do I use allocator-aware containers in C++?

Using Allocator-Aware Containers

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How do I use allocator-aware containers in C++?

Using Allocator-Aware Containers

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