title: Why is TSP NP-hard while the Hamiltonian path NP-complete?
body: <p>Why aren't these 2 problems, namely <a href="https://en.wikipedia.org/wiki/Travelling_salesman_problem" rel="nofollow noreferrer">TSP</a> and <a href="https://en.wikipedia.org/wiki/Hamiltonian_path_problem" rel="nofollow noreferrer">Hamiltonian path problem</a>, both NP-complete?</p>
  
  <p>They seem identical.</p>