title: ' ' was not declared in this scope
body: <p>I'm new and I really can't understand the meaning of "not declared in scope" error. I tried declaring these as functions and also by using "" to show a function but it did not compile and run. Here are the errors:</p>
  
  <p>In function 'int main()':</p>
  
  <p>[Error] 'random' was not declared in this scope</p>
  
  <p>[Error] 'sound' was not declared in this scope</p>
  
  <p>[Error] 'delay' was not declared in this scope</p>
  
  <p>[Error] 'nosound' was not declared in this scope</p>
  
  <p>[Error] 'BLINK' was not declared in this scope</p>
  
  <p>[Error] 'textattr' was not declared in this scope</p>
  
  <pre><code>#include&lt;stdio.h&gt;
  
  #include&lt;iostream&gt;
  
  #include&lt;dos.h&gt;
  
  #include&lt;conio.h&gt;
  
  #include&lt;stdlib.h&gt;
  
  using namespace std;
  int main ()
  {
      int count=50;
      while(count--)
      {
      sound(90*random(10));
      delay(100);
      nosound();
      textattr(random("16")+'a'+BLINK);
      cprintf("KSHITIJ");
      }
  }
  </code></pre>