title: Flight Search using A* algorithm; suitable cost and huristic
body: <p>I'm going to find the quickest and the cheapest flights using A* algorithm, when it is given the source and destination airports. These two paths will be found separately.</p>
  
  <p>To find the quickest path , I'm going to use average travel time between the source and destination airports as the huristic value.</p>
  
  <p>I have few problems:</p>
  
  <ol>
  <li><p>could you please tell me, where can I find a data source , which has average travel times between every airport pair? Or any data source which contains the distances between every airport pair?</p></li>
  <li><p>Finding the cheapest path is not easy as I thought.All the fares can not be used as a cost of an edge(flight leg is taken as an edge).Because some fares are applicable to more than one flight leg .e.g: from SFO to JFK via BOS  100$.</p>
  
  <p>2.1 Could you please suggest me a way of finding the cheapest path/paths?</p>
  
  <p>2.2 Is A* is suitable for this?</p>
  
  <p>2.3 If it is suitable what is the most appropriate huristic value to be used? </p>
  
  <p>2.4 Is there any way to get a data source containing average fare between each airport pair?</p></li>
  </ol>
  
  <p>Great Help friends...
  Thanks in Advance!!!</p>