<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><br></div><div>Origin means (0,0) or plain 0 in English. </div><div><br></div><br><div><div>On Jun 22, 2012, at 2:42 PM, Roelof Wobben wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite">
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Hello, <br>
<br>
I try to make this exercise : <br>
<br>
<div class="SIntrapara"><a name="(counter._mix._(exercise._mix4))"></a><span style="font-weight: bold;">Exercise</span> 76: A programmer has
chosen to represent locations as Cartesian points or just points:</div>
<div class="SIntrapara">
<blockquote class="SCodeFlow">
<table class="RktBlk" cellspacing="0">
<tbody>
<tr>
<td><span class="RktCmt">;</span><span class="RktCmt"> </span><span class="RktCmt">Location is one of:</span></td>
</tr>
<tr>
<td><span class="RktCmt">;</span><span class="RktCmt"> </span><span class="RktCmt">–</span><span class="RktCmt"> Posn</span></td>
</tr>
<tr>
<td><span class="RktCmt">;</span><span class="RktCmt"> </span><span class="RktCmt">–</span><span class="RktCmt"> Number</span></td>
</tr>
<tr>
<td><span class="RktCmt">;</span><span class="RktCmt"> </span><span class="RktCmt">interp. Posn are positions on the
Cartesian grid,</span></td>
</tr>
<tr>
<td><span class="RktCmt">;</span><span class="RktCmt"> </span><span class="RktCmt">Numbers are positions on the number
line </span></td>
</tr>
</tbody>
</table>
</blockquote>
</div>
<div class="SIntrapara">Design the function <span class="RktSym">in-reach</span>,
which determines whether or not a given location’s distance to the
origin is strictly less than some constant<span class="RktSym">R</span>.<br>
<br>
So I must design a function called in-reach.<br>
<br>
Am I right I need to use two structs (Posn) . One for the given
location and one for the origon ?<br>
<br>
Regards, <br>
<br>
Roelof<br>
<br>
<br>
</div>
<br>
</div>
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