How to make a spaced line of strings from a vector in C++

Question

I want to make a line like this hello my name sounds very fancy from a vector of these words (std::vector<std::string> myvector = {"hello", "my", "name", "sounds", "very", "fancy"}).

What is the most efficient way to perform such convertion without inserting redundant spaces, as would happen if I used

for (auto element : v) {
    std::cout << word_from_vector << ' ';
}

?

Answer 1

If your compiler supports C++ 20 then you can write the range-based for loop the following way to eliminate the trailing space

for ( bool next = false; const auto &element : myvector ) 
{
    if ( next )
    {
        std::cout << ' ';
    }
    else
    {
        next = true;
    }
    std::cout << element;
}

Otherwise you could use the ordinary for loop like

for ( size_t i = 0; i < myvector.size(); i++ )
{
    if ( i != 0 ) std::cout << ' ';
    std::cout << myvector[i]
}