title: How do you call error in C++?
body: <p>I'm working on Bjarne Stroustrup's Chapter 3 in Programming: Principles and Practice Using C++</p>
  
  <blockquote>
    <p>Prompt the user to enter the age or the recipient and assign it to an int
    variable age. Have your program write "I hear you just had a birthday
    and You are age years old." If age is 0 or less or 110 or more, call
    error("you're kidding!").</p>
  </blockquote>
  
  <pre><code>cout&lt;&lt;"Enter the age of "&lt;&lt;friend_name&lt;&lt; ".\n";
  int age=0;
  cin&gt;&gt;age;
  if (age==0)
      cout&lt;&lt;"you're kidding!";
  
  if (age&gt;=110)
      cout&lt;&lt;"you're kidding!";
  
  if (age!=0, 110)
      cout&lt;&lt;"I hear you just had a birthday and you are " &lt;&lt;age&lt;&lt; " years old.\n";
  </code></pre>
  
  <p>I tried to do the code above but It kept giving me </p>
  
  <blockquote>
    <p>"you're kidding! I hear you you just had a birthday and you are 0 years old" </p>
  </blockquote>
  
  <p>but I don't think that is right. I think it's supposed to do one or the other and not both but I don't know how to make it do that.</p>