#include <boost/range/adaptor/indexed.hpp>
    #include <vector>
    #include <string>
    #include <iostream>
    
    std::vector<std::string> strings{10, "Hello"};
    int main(){
        strings[5] = "World";
        for(auto const& el: strings| boost::adaptors::indexed(0))
        {
          std::cout << el.index() << ": " << el.value() << std::endl;
        }
    }