title: Why g++ compiler is not able to find unique_ptr?
body: <p>I am trying to compile a small C++ code which invloves unique_ptr as given below.</p>
  
  <pre><code>#include &lt;iostream&gt;
  #include &lt;memory&gt;
  
  using namespace std;
  
  int main()
  {
      unique_ptr&lt;int&gt; p1(new int);
  }
  </code></pre>
  
  <p>when I tried to compile the code using g++, it is throwing up 'unique_ptr' was not declared in this scope. I was trying to compile on Linux box. even I tried with '-std=c++11' option. It was saying 'unrecognized command line option -std=c++11'. Can any one please let me know how to fix this?</p>