uppercasing each words(each strings) in a vector

str_upp.cpp

#include <iostream> /// std::cout // std::endl
#include <vector> /// std::vector
#include <cctype> /// toupper();

int main()
{
    std::vector<std::string> words; /// initialized a empty vector of string
    std::string temp_word; /// stores an temporary input 

    while(std::cin >> temp_word)
        words.push_back(temp_word); /// pushes to word element

    for(auto &w : words) { /// for every w in words /// deduces or assumes that w is a reference string that is bound to words
        for(auto &c : w) { /// for every c in w /// deduces or assumes that c is a reference char that is bound to w
            c = toupper(c); /// converts every reference char to uppercase
        }
    }

    for(auto w_upper : words) /// for every w_upper in words /// deduces or assumes that w_upper is a string
        std::cout << w_upper << std::endl; /// displays the value

    return 0; /// successfull exit
}