How do I merge two containers efficiently with std::unordered_map in performance-sensitive code?

Merging two containers efficiently in C++ can be crucial for performance-sensitive applications. When using `std::unordered_map`, you can achieve this by leveraging the map's underlying hash table structure. Here’s how you can do it:

First, ensure that both containers are of type `std::unordered_map` (or can be converted into this type). Then, you can use the `insert` member function to merge them. Here’s a concise example:


    #include <iostream>
    #include <unordered_map>

    int main() {
        std::unordered_map map1 = {
            {1, "One"},
            {2, "Two"}
        };

        std::unordered_map map2 = {
            {3, "Three"},
            {4, "Four"}
        };

        // Merging map2 into map1
        map1.insert(map2.begin(), map2.end());

        // Displaying the merged map
        for (const auto& pair : map1) {
            std::cout << pair.first << ": " << pair.second << std::endl;
        }

        return 0;
    }

How do I merge two containers efficiently with std::unordered_map in performance-sensitive code?

Popular Topics

Recent Languages

How do I merge two containers efficiently with std::unordered_map in performance-sensitive code?

Related Questions

Popular Topics

Recent Languages