title: How to find if a given key exists in a C++ std::map
body: <p>I'm trying to check if a given key is in a map and somewhat can't do it:</p>
  
  <pre><code>typedef map&lt;string,string&gt;::iterator mi;
  map&lt;string, string&gt; m;
  m.insert(make_pair("f","++--"));
  pair&lt;mi,mi&gt; p = m.equal_range("f");//I'm not sure if equal_range does what I want
  cout &lt;&lt; p.first;//I'm getting error here
  </code></pre>
  
  <p>so how can I print what is in p?</p>