title: In C++ check if std::vector<string> contains a certain value
body: <p>Is there any built in function which tells me that my vector contains a certain element or not
  e.g.</p>
  
  <pre><code>std::vector&lt;string&gt; v;
  v.push_back("abc");
  v.push_back("xyz");
  
  if (v.contains("abc")) // I am looking for one such feature, is there any
                         // such function or i need to loop through whole vector?
  </code></pre>