This page gives solutions of the MPFR team to the 
<a href="http://www.cs.ru.nl/~milad/manydigits/sample_questions.php">
practice problems</a>
of the <a href="http://www.cs.ru.nl/~milad/manydigits/">Many Digits Friendly
Competition</a>.
A companion page exists for the
<a href="competition.html">competition problems</a>.

The given timings were obtained on <tt>harif.cs.ru.nl</tt>,
a mono-processor AMD Opteron 144 machine running
  Debian GNU/Linux "sid" unstable i386 (32 bit mode),
  which has 4GB of RAM.
We used gmp-4.1.4, mpfr-20050920 (cvs version from 20 Sep 2005),
and mpfi-1.3.3 (adapted to mpfr-cvs).

The methods used in the different programs are explained
<a href="practice.pdf">here</a>.

We recall here the rule to find the ``optimal'' parameter N: "find the
N closest to the default value so that the cpu time fits between 2 seconds
and 2 minutes".

<p>

<center>
<table border="1">
<tbody>
<tr><td>problem</td><td>N</td><td>cpu time</td><td>first..last digits</td></tr>
<tr><td><a href="p01a.c">P01</a></td><td>5</td><td>18.062</td><td>678...645</td></tr>
<tr><td><a href="p02a.c">P02</a></td><td>6</td><td>23.310</td><td>772...944</td></tr>
<tr><td><a href="p03a.c">P03</a></td><td>5</td><td>8.251</td><td>410...508</td></tr>
<tr><td><a href="p04a.c">P04</a></td><td>5</td><td>3.271</td><td>999...658</td></tr>
<tr><td><a href="p05a.c">P05</a></td><td>5</td><td>5.213</td><td>104...929</td></tr>
<tr><td><a href="p06a.c">P06</a></td><td>5</td><td>8.056</td><td>490...892</td></tr>
<tr><td><a href="p07a.c">P07</a></td><td>6</td><td>13.853</td><td>226...815</td></tr>
<tr><td><a href="p08a.c">P08</a></td><td>5</td><td>5.466</td><td>613...362</td></tr>
<tr><td><a href="p09a.c">P09</a></td><td>5</td><td>18.864</td><td>000...306</td></tr>
<tr><td><a href="p10a.c">P10</a></td><td>5</td><td>6.684</td><td>000...000</td></tr>
<tr><td><a href="p11a.c">P11</a></td><td>5</td><td>22.439</td><td>145...390</td></tr>
<tr><td><a href="p12a.c">P12</a></td><td>5</td><td>14.292</td><td>712...771</td></tr>
<tr><td><a href="p13a.c">P13</a></td><td>4</td><td>8.804</td><td>824...580</td></tr>
<tr><td><a href="p14.c">P14</a></td><td>2</td><td>29.591</td><td>999...999</td></tr>
<tr><td><a href="p15a.c">P15</a></td><td>5</td><td>6.300</td><td>392...432</td></tr>
<tr><td><a href="p16a.c">P16</a></td><td>5</td><td>68.860</td><td>326...023</td></tr>
<tr><td><a href="p17a.c">P17</a></td><td>3</td><td>3.070</td><td>014...886</td></tr>
<tr><td><a href="p18a.c">P18</a></td><td>5</td><td>24.165</td><td>577...897</td></tr>
<tr><td><a href="p19a.c">P19</a></td><td>6</td><td>3.372</td><td>143...250</td></tr>
<tr><td><a href="p20d.c">P20</a></td><td>6</td><td>27.138</td><td>1</td></tr>
<tr><td><a href="p21a.c">P21</a></td><td>5</td><td>15.096</td><td>219...495</td></tr>
<tr><td><a href="p22.c">P22</a></td><td>3</td><td>15.931</td><td>430...309</td></tr>
<tr><td><a href="p23.c">P23</a></td><td>2</td><td>2.698</td><td>9844998112</td></tr>
<tr><td><a href="p24.c">P24</a></td><td>2</td><td>0.196</td><td>2933301369</td></tr>
</tbody>
</table>
</center>
The source files need the <a href="many.h"><tt>many.h</tt></a> header file,
P23 and P24 need <a href="gauss.h"><tt>gauss.h</tt></a> too,
and P22 needs the <tt>intlib</tt> library from Laurent Fousse (not yet
available).