title: Convert vector of string between ranges to a delimited string(boost allowed)
body: <p>I have a vector of strings with a size of 10. I want to join it to a string from index 3 to 6 with space as delimiter. I know <code>boost::algorithm::join</code> could do it with the whole vector, but I want something that does it on a specific range with minimal copy and optimal efficiency. i know lot of stringstream based solution but i want something that doesn't have overhead of stringstream to string.</p>