title: How to find if two linked list intersect each other?
body: <blockquote>
    <p><strong>Possible Duplicate:</strong><br>
    <a href="https://stackoverflow.com/questions/2216666/finding-the-intersecting-node-from-two-intersecting-linked-lists">Finding the intersecting node from two intersecting linked lists</a>  </p>
  </blockquote>
  
  
  
  <p>Given two large linked list, which </p>
  
  <ol>
  <li>a) Do intersect </li>
  <li><p>b) May intersect</p>
  
  <p>find the node that is at the intersection.  By intersection I don't mean their values. I mean a node is common. i.e. two different nodes from list A and list B point to same node</p></li>
  </ol>
  
  <p>E.g. </p>
  
  <pre><code>3-&gt;1-&gt;2-&gt;4-&gt;NULL
        ^
        |
  5-&gt;4-&gt;3
  
  3-&gt;1-&gt;2-&gt;NULL
        ^
        |
  9-&gt;2-&gt;3
  </code></pre>
  
  <p>PS :
   3. Hash tables not allowed.</p>
  
  <ol start="4">
  <li>Obvious brute force method N*M comparisons is ruled out. We want better solution.</li>
  </ol>