How do I merge and splice sequences with std::multimap?

In C++, the std::multimap container can be used to store key-value pairs where multiple keys can correspond to the same value. If you want to merge and splice sequences of std::multimap, you can utilize its built-in methods effectively. This tutorial will demonstrate how you can achieve this with practical examples.

Merging and Splicing with std::multimap

To merge two multimaps, you can use the insert method, which allows you to insert the elements of one multimap into another. For splicing, you'll typically remove elements from one multimap and insert them into another.

Here’s an example of how to merge and splice std::multimap objects:


        #include <iostream>
        #include <map>

        int main() {
            std::multimap map1 = {
                {1, "apple"},
                {2, "banana"},
                {2, "blueberry"},
            };

            std::multimap map2 = {
                {1, "apricot"},
                {3, "cherry"},
            };

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

            // Displaying merged map1
            std::cout << "Merged multimap:\n";
            for (const auto &pair : map1) {
                std::cout << pair.first << ": " << pair.second << "\n";
            }

            // Splicing - Moving elements with key 2 from map1 to map3
            std::multimap map3;
            auto range = map1.equal_range(2);
            map3.insert(range.first, range.second);
            map1.erase(range.first, range.second);

            // Displaying map1 after splicing
            std::cout << "After splicing:\n";
            for (const auto &pair : map1) {
                std::cout << pair.first << ": " << pair.second << "\n";
            }

            // Displaying spliced map3
            std::cout << "Spliced multimap (map3):\n";
            for (const auto &pair : map3) {
                std::cout << pair.first << ": " << pair.second << "\n";
            }

            return 0;
        }

How do I merge and splice sequences with std::multimap?

Merging and Splicing with std::multimap

Popular Topics

Recent Languages

How do I merge and splice sequences with std::multimap?

Merging and Splicing with std::multimap

Related Questions

Popular Topics

Recent Languages