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    <div class="moz-cite-prefix">Um ... To the other people giving
      hints:  Don't forget that in the sequence *of lines in the
      program* you have to state the base case(s) *first*, certainly in
      Haskell, which goes through the lines in order, until it finds a
      match.<br>
      <br>
      That's what I meant when I said "first do the base case(s), then
      the rest":  first *in the program order*, if not necessarily in
      the conceptual structure.  So for the depth-first binary tree
      which Joel Neely pointed out, *first* you must deal with the base
      case that the node being looked at is actually a leaf; *only then*
      can you deal with the fact that in general the algorithm has the
      structure <process left descendants><process this
      node><process right descendants>.<br>
      <br>
      So if you try <move stack off of bottom><move
      bottom><place stack on bottom>, the first part will
      either enter an endless loop or will generate an error, because it
      doesn't have a base case.  (No pun on "base" intended.)<br>
      <br>
      On 2/17/15 4:05 AM, Joel Neely wrote:<br>
    </div>
    <blockquote
cite="mid:CAEEzXAifYjbjBhPB=nk-hmNvrzf-cSSVrXQeC6shBnA7Z9=EGA@mail.gmail.com"
      type="cite">
      <div dir="ltr">
        <div class="gmail_extra">
          <div class="gmail_default"
            style="font-family:georgia,serif;font-size:small">​Let's
            tweak your answers​ just a bit, calling the three pegs the
            "source", "goal", and "spare" pegs:</div>
          <br>
          <div class="gmail_quote">On Tue, Feb 17, 2015 at 5:23 AM,
            Roelof Wobben <span dir="ltr"><<a moz-do-not-send="true"
                href="mailto:r.wobben@home.nl" target="_blank">r.wobben@home.nl</a>></span>
            wrote:<br>
            <blockquote class="gmail_quote" style="margin:0px 0px 0px
0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">
              <div bgcolor="#FFFFFF" text="#000000">- Where do I move
                the bottom (largest disk) ? <br>
                <br>
                To the last peg, which do not contain any disk then
                <div class="gmail_default"
                  style="font-family:georgia,serif;font-size:small;display:inline">​
                  .</div>
              </div>
            </blockquote>
            <div><br>
            </div>
            <div>
              <div class="gmail_default"
                style="font-family:georgia,serif;font-size:small;display:inline">From
                the source peg to the goal peg, which will</div>
              <span style="font-family:georgia,serif">/must</span>
              <div class="gmail_default"
                style="font-family:georgia,serif;display:inline"> not
                contain any disks.​</div>
               </div>
            <blockquote class="gmail_quote" style="margin:0px 0px 0px
0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">
              <div bgcolor="#FFFFFF" text="#000000">
                <div class="gmail_default"
                  style="font-family:georgia,serif;font-size:small;display:inline">​</div>
                <br>
                <br>
                - What must happen before I can move the bottom disk ? <br>
                <br>
                I have to move the disk which above that disk. <br>
              </div>
            </blockquote>
            <div><br>
            </div>
            <div>
              <div class="gmail_default"
                style="font-family:georgia,serif;font-size:small;display:inline">Move
                everything else from ____ to ____.​</div>
               </div>
            <blockquote class="gmail_quote" style="margin:0px 0px 0px
0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">
              <div bgcolor="#FFFFFF" text="#000000"> <br>
                - What must happen after I move the bottom disk ?<br>
                <br>
                All the other disk must be placed above that disk. <br>
              </div>
            </blockquote>
            <div><br>
            </div>
            <div>
              <div class="gmail_default"
                style="font-family:georgia,serif;font-size:small;display:inline">​
                Move everything else from ____ to ____.​</div>
               </div>
          </div>
          <br>
          <div class="gmail_default"
            style="font-family:georgia,serif;font-size:small">​So more
            questions/hints:</div>
          <div class="gmail_default"
            style="font-family:georgia,serif;font-size:small">
            <ol>
              <li>How do you fill in the blanks?<br>
              </li>
              <li>How do you put the three statements in order?<br>
              </li>
              <li>How many disks does each statement talk about?<br>
              </li>
            </ol>
          </div>
          <div class="gmail_default"
            style="font-family:georgia,serif;font-size:small"><br>
          </div>
          <div class="gmail_default"
            style="font-family:georgia,serif;font-size:small">-jn-</div>
          <div class="gmail_default"
            style="font-family:georgia,serif;font-size:small">​</div>
          <br>
          <br clear="all">
          <div><br>
          </div>
          -- <br>
          <div class="gmail_signature">Beauty of style and harmony and
            grace and good rhythm depend on simplicity. - Plato</div>
        </div>
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      <pre wrap="">_______________________________________________
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</pre>
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