Find the different characters present in a string

Question

Is there any way to find the all the unique characters present in a string without finding all the occurrences of the string ? For example, Let it be s

Answer 1

Make a set of characters and put all items from string to it, then you will have set with "alphabet" of your string.

E.g.:

#include 
#include 
#include 

int main(void)
{
    std::string a = "mississippi";
    std::set alphabet;
    alphabet.insert(a.begin(), a.end());
    std::cout << "Set of chars has " << alphabet.size() << " items." << std::endl;
    for (auto a : alphabet)
    {
        std::cout << a << std::endl;
    }
}

Original string is not modified in that example and there is no need to pre-sort.