title: Error : "No match for 'operator <<' (operand types are std::istream)
body: <p>This is my first StackOverflow and happy to join.
  I'm currently studying C++ with Stroustrup's "Programming and Practice using C++" and for now we are using a library he created (#include "std_lib_facilities.h")</p>
  
  <p>I finished an exercise and got this error
  "No match for 'operator &lt;&lt;' (operand types are std::istream)"</p>
  
  <p>The program I wrote may not be perfect yet but I can't even compile it at this point. I've read in other posts something about "overload operator" but I don't understand what it means and specifically why in my other files this does not happen even with the same library loaded.</p>
  
  <pre><code>#include "../../std_lib_facilities.h"
  
  int main()
  {
      double val1 = 0;
      double val2 = 0;
  
      cin &lt;&lt; val1 &lt;&lt; val2 &lt;&lt; endl;
  
      if (val1&gt;val2)
          cout &lt;&lt; val1 &lt;&lt; " is larger than " &lt;&lt; val2 &lt;&lt;endl;
      else
          cout &lt;&lt; val1 &lt;&lt; " is smaller than " &lt;&lt; val2 &lt;&lt;endl;
  </code></pre>
  
  <p>}</p>