The question seems to be asking how to join two...

The question seems to be asking how to join two unordered maps in C++. Here's an example of how you can merge two unordered maps:

#include <iostream>
#include <unordered_map>

int main() {
    std::unordered_map<int, std::string> map1 = {{1, "one"}, {2, "two"}, {3, "three"}};
    std::unordered_map<int, std::string> map2 = {{4, "four"}, {5, "five"}, {6, "six"}};

    // Merge the two unordered maps
    map1.insert(map2.begin(), map2.end());

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

    return 0;
}

This code demonstrates how to merge two unordered maps (map1 and map2) by using the insert() method. The insert() method takes a range of elements as its arguments, in this case, the beginning and end iterators of map2. After merging the maps, the code prints the key-value pairs of the resulting map.