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<div class="moz-cite-prefix">10^(10^10) is a 1 followed by ten
billion zeros. Naively evaluating that to an integer is going to
cause time and memory problems in any software that supports
arbitrary size integers - as Bob Ippolito said, it's going to take
about 3.86gb just to store such a number in binary. Even math
software (Maple) rejects an attempt to evaluate it directly -
sensibly, the "arbitrary size" integers in Maple do have a
maximum.<br>
<br>
<blockquote type="cite">
<div>
<div> h> import Data.Number.BigFloat</div>
<div> h> ((10 :: BigFloat Eps1)^10)^10</div>
<div> 1.e100</div>
</div>
</blockquote>
and<br>
<blockquote type="cite">If you are only solving 10^(10^10) why not
construct a string with "1" followed by a 100 zeroes?</blockquote>
<br>
10^(10^10) isn't the same as (10^10)^10, which is a 1 followed by
100 zeros, easy to evaluate to an integer in Haskell.<br>
<br>
Evaluating (10 :: BigFloat Eps1)^(10^10) runs into the same
problems as 10^(10^10):<br>
<br>
Prelude> 10^(10^10)<br>
<interactive>: out of memory<br>
[restart]<br>
<br>
Prelude> 10.0^(10^10)<br>
Infinity<br>
Prelude> 10.0**(10.0^10)<br>
Infinity<br>
Prelude> import Data.Number.BigFloat<br>
Prelude Data.Number.BigFloat> (10 :: BigFloat Eps1)^(10^10)<br>
<interactive>: out of memory<br>
<br>
Maple> 10.0^(10^10);<br>
<img src="cid:part1.05070400.03070406@gmail.com" alt=""><br>
Maple> 10^(10^10);<br>
Error, operation failed. Integer exponent too large.<br>
<br>
Graham<br>
<br>
On 21/09/2013 10:02 PM, yi lu wrote:<br>
</div>
<blockquote
cite="mid:CAKcmqqx_9NO8gkFeLYxFXVqNEUDnqURAv8wgn2Q7u3L2ch2CiA@mail.gmail.com"
type="cite">
<div dir="ltr">
<div>I am checking whether a number equals 10^(10^10).<br>
<br>
</div>
Yi<br>
</div>
<div class="gmail_extra"><br>
<br>
<div class="gmail_quote">On Sun, Sep 22, 2013 at 7:11 AM, KC <span
dir="ltr"><<a moz-do-not-send="true"
href="mailto:kc1956@gmail.com" target="_blank">kc1956@gmail.com</a>></span>
wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">
<div dir="ltr">
<div>
<div>Have you compared the solution to other languages?<br>
<br>
</div>
If you are only solving 10^(10^10) why not construct a
string with "1" followed by a 100 zeroes?<br>
<br>
</div>
In other words, what is this being used for?<br>
<br>
</div>
<div class="gmail_extra"><br>
<br>
<div class="gmail_quote">
<div class="im">On Sat, Sep 21, 2013 at 3:32 PM, yi lu <span
dir="ltr"><<a moz-do-not-send="true"
href="mailto:zhiwudazhanjiangshi@gmail.com"
target="_blank">zhiwudazhanjiangshi@gmail.com</a>></span>
wrote:<br>
</div>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">
<div class="im">
<div dir="ltr">
<div>Why is it so slow to solve "10^(10^10)" in
Haskell?<span><font color="#888888"><br>
<br>
</font></span></div>
<span><font color="#888888">Yi<br>
</font></span></div>
<br>
</div>
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</blockquote>
</div>
<span class="HOEnZb"><font color="#888888"><br>
<br clear="all">
<br>
-- <br>
--<br>
Regards,<br>
KC
</font></span></div>
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