title: return value is undefined in C
body: <p>Not sure if I'm overthinking for this, but how would I return something undefined when the parameter is not in the range that needs to be?</p>
  
  <p>I'm trying to do:</p>
  
  <pre><code>uint64_t function(uint64_t Value, uint64_t N) {
     uint64_t result = 0;
  
     if (N &gt; 0){
       //do something;
       return result;
     }
     else{
       return result is undefined;
     }
  }
  </code></pre>
  
  <p>How do I return N is undefined?</p>