#include <string>
#include <algorithm>
#include <iostream>

int main()
{
    std::string string1 = "kanu";
    std::string string2 = "charu";
    std::string string_difference, string_intersection, string_union;

    std::sort(string1.begin(), string1.end());
    std::sort(string2.begin(), string2.end());

    std::set_difference(string1.begin(), string1.end(), string2.begin(), string2.end(), std::back_inserter(string_difference));
    std::cout << "In string1 but not string2: " << string_difference << std::endl;

    std::set_intersection(string1.begin(), string1.end(), string2.begin(), string2.end(), std::back_inserter(string_intersection));
    std::cout << "string1 intersect string2: " << string_intersection << std::endl;

    std::set_union(string1.begin(), string1.end(), string2.begin(), string2.end(), std::back_inserter(string_union));
    std::cout << "string1 union string2: " << string_union << std::endl;
}