title: NP-Complete reduction (in theory)
body: <p>I want to embed 3 NP-Complete problems(2 of them are known to be NP-Complete, 1 of them is my own idea). I saw "<a href="https://stackoverflow.com/questions/141779/solving-the-np-complete-problem-in-xkcd">this question</a>" and got idea about reinterpreting embedding problems in theory:</p>
  
  <ul>
  <li>The Waiter is The Thief.</li>
  <li>Tables are store.</li>
  <li>Foods are valued items which has different weight.</li>
  <li>Thief know all the items' price and weight before the robbery.</li>
  <li>His target is most efficient robbery(max capacity of knapsack used, most valued items got) with robbing(getting at least 1 item) all stores(shortest way to completing robbery tour, also visit each store 1 time).</li>
  </ul>
  
  <p>This part is embedding 2 NP-Complete problems.</p>
  
  <p>My idea is, that more items mean more bag weight. More bag weight slow downs the thief exponentially. So another target of the thief should be finishing the robbery as quickly as he/she can.</p>
  
  <p>At this time, I'm not sure that my idea is actually NP-Complete. Maybe, "gravity" is not a NP-Complete Problem alone. But maybe it is in this context of the travelling salesman and knapsack problem.</p>
  
  <p>So my questions are:</p>
  
  <ol>
  <li><p>Is the slowing down of the thief NP-complete, too?</p></li>
  <li><p>Is it possible to reduce those three embedded problems to a simple NP-complete problem?</p></li>
  </ol>