This question already has answers here:
BigInteger in C?
(4 answers)
Closed 8 years ago.
I'm looking for a way so that I can get big numbers.
I want to calculate 38^n for n>4000
So is there any way to do this?
Kindly help me.
Look for a BigInt library like this one if the unsigned long long (64-bit integer) does not fit your needs.
Since 38^4000 =
13626567354997617056329313518572669871071170880583693359544272980041303981882434734538430960058767177295025923983566648755876881186325460368486197224167007060233768247052629486933889789012295518920202064862370213656621579461608833913900821509100620666110600996588831934295625624174881269739475099253543291971949351958375909705904924125614847402331728307491174234130043557765333856587852136763450074228033057943275251763474040244718003871446278851718437538753553972738188449864081284199350852720967506441771879828977604092893701331872025324453791540567000401652841385183230548306942426747811381344952202704995790135045091236882434632638273097622784399474964071260288840973524580293683712707126132726032058096115050808212994474874887195248086357178602097170972380906461711265125678088349923203375968414475787300592583696065816150079128755226670110739203817178406747936072376786260989121289233458431976862204647875012437031767751018704749869460607366074818959142212892198396374773980500350327658780222474479129859007194457457829138631699788091425513210781560184664312254850195910716334354324281366251167877851974205334475355985568256387781089509361002196647952275789359155111023451749451415734405096655278295174255960345304122475081165484445003142760913586534250626764015379905517010658444442626228678332925600616931303695695506161883152099899363859336729182377570281814058896416875807664402882868124355445335565905063833617714010822965856571393423962785717867701811630985000479945840574458836679738068978432208205049488474929993540051593774645379459275410621407737459680323962561140718740797900009352381301734433124145413190718954715078693891773766465543820020118333909425037946747920952112324716580163881088322718499979305631739834146130913408498900815005646996682256912339033205133816486824614258926495495812784036447453990264570960357479488597566262100857318557132063094971671138328081636423205300001440991841875093227157189180046979201235997836871115178473793331951908545162574227413951298558070125899512700390047047940487152449438682512124512374465180907633872133729735427824770312681013603101057078687642650433926086042263469811785972516780935001257979167301396531650578909144617556401661596286655000890845598227443074432224649650421444669509917690850588828467680365214374983571440413011029311538006314308009334022145676697106884765702897820392205002104976510511690662873648924905859206045090301538364495227369714240000327397892685270724477432224051710235161915341380166322505403047479921207485985826617144630062427543646106264207676267960138097995365712065699367252327692166917027162817512355112577817759333185119496357726652263574955692412766427791636621561003248143162088338810765811925034175243098253477183777981530119336600325069531470597361199726340530012493284901312472359938906404036536403970381273042347532022592036037374925652036435508211829648726060002645001171965651585268749073280713101532058063840348319740158848595441587678957522413199351039043113142029907129705744137232342011968704198807114940460676009450036521225461344010852618106239118154966331660057415602614793721826584529397251289749725656538096388399695143315928518563068548192735206544682378537520506418007926073285706849973274222076317373033059304200101911951067149937028894562722109537797411167898225856420348308410350603384055632474339567057703010340688068370821291318903177717596801407315734010878564418695310254546381520276678538725157608043309023441709322160712160377986536483006949768428055070012131321307517369398293559849470345086292046748890778373027131007888477361435703338650286281943866790521895536089587012314596482938225348353910513764482608946308253045592163757729525262326745493201953185303485264102739959029696399931572287438132772357749175882967079565029225741296582036140259021566923027054743911617278986639492312193679025969190891540930024189366778105054430929215092236023487686440492543667079519662985565417362492072592025055258819162704173072662013949276074302392094104918002731442385963738154377544394436144830710895941012427657480393526992952298836599116927265835864794883149357772532128926114623377650330127681469398680908197842808781573649462943403899309504315010053951097502630531047921616001572581816853481632903644705002543359747980637999901147726746920478281033260422246532219801930828506609799922586505464736354853965408705166237575268884142550705915838361403803760633861291439873689266312094985645627825768264532068068383940009347237832839084518620736293338032805140684318825609037052029320710069076942327055511619384729507413979366221173731875081583527606225142331708054058056316566268463694297799208229967327456031980737573803309723678915050699869715272912792497268191176053411510542893000088350086703903267923064151320399321810627158761446660416500169785103732189707448149719408203646028631800570100383545558186048239744484408082627734589940230907845416949939893008652775458505691974437891034384581573026445318317396853368414228897325531497788743229729964241347151442038312944349207021462075732646443668171786595400861104506016915734670330338318506940647492024589840270503991235013262662584958056139456884168786647861529375426433055592755996647363095606998572938173742273727647855395827384610580791486231441743966364638926656177574517783395990477645234920662029069130520169839954328852889679297698894440289360920229577366598674693945253544348773443008431294122902200275761539883366488016392721682618754525310713687607682663191813572550150753228158785842023491267134367643177590897108661282968536031908401081453990449167116430269199694437799218382709284611544863462398344387527482864615346690281888178491568067973361859477877403761036289855293359103434207477896715048195648273965669239199756276403324120343903889368419203819744433704771664793914154135622085625251617910720554457686952006577578494073537754699513783351789231152535131897837873522492614650699226752457363727673079692328753548477123197857803197559269831202493927130425819248457221653733937060671839872590344351995222910813966529070591698808960588220021008665427193485211880949161819748058663187983592657186472030052147851033490886803897240924656263389646409848702846770248392608384734172415681411506756891468425081693839740848739676180437868697906407065835441491240347225077345140389966302714596712069918261923483301431653997283019346596069376
You definitely need some kind of big int library. You can find one quite easily on Google or even (if you plan only specific operations), write one on your own. For instance, the above result comes from my own calculator, which supports big integer evaluations.
Related
This question already has answers here:
C++ cache aware programming
(10 answers)
Closed 7 years ago.
I am profiling my code on various CPUs running Windows7 and my results so far suggest that I need to tune a buffer size proportional to the machine's L2CacheSize or L3CacheSize. Is there a way to obtain these parameters from C++?
You can use the GetLogicalProcessorInformation function to get that. It returns an array of SYSTEM_LOGICAL_PROCESSOR_INFORMATION structures which contain a CACHE_DESCRIPTOR structure, which provides the cache size information.
Closed. This question needs to be more focused. It is not currently accepting answers.
Want to improve this question? Update the question so it focuses on one problem only by editing this post.
Closed 9 years ago.
Improve this question
I am supposed to build a program for storing and handling huge integers. I know that there are many answers out there but I need ideas that I can implement easily, bearing in mind that I can use any of the basic concepts of C/C++.
How should I go about it?
This is the first time I am asking a question here so please correct me if I am wrong about anything.
Edit: Actually what I wanted to know was how should I go about storing a huge integer... Obviously an array is what comes to mind at first glance but are there any other methods out there at the basic level?
EDIT2: I came across a very nice solution to this problem a while ago, but was just a bit lazy to put it on here. We can use the concept of number systems to deal with huge numbers. We can declare an array that holds the co-efficient of powers of 256, thus obtaining a base 256 system. We can then use fundamental concepts like those of the various number systems to obtain our required results.
Matt McCutchen has a Big Integer Library
If you want to do this yourself his code would be a great starting point. As you can overload arithmetic operators in C++ it is not too difficult to make a new BigInteger class and make this handle any number of bits per integer.
There is also a stack overflow answer to this question: here
I consider this as a question about theory, as such I suggest to browse the internet using the right keywords for documents/articles or to take a sneak peek at libraries that are implementing this feature and are well tested, this projects also tend to offer a mailing list or a forum where developers can communicate, it can be a good place to start writing about this stuff.
This question already has answers here:
Bignum libraries for windows?
(4 answers)
Closed 9 years ago.
Is there a library that can be implemented relatively easily in windows?
I made a few functions a while ago which used arrays of numbers to get the desired outcome. I might work at them when I get the time.
But is there any such feature already available that can be implemented into c++ easily?
Apparently people have had luck with using the GNU Multiple Precision Arithmetic Library for Windows.
This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
Dump facility in C++ like var_dump() in PHP?
I'm not sure does C++ even allow this kind of thing, but I was wondering, could it be possible to write a generic function that could output any type array (std::vector) as plain text, as long as I write myself each of the types output function, for example std::string, float, int, etc.
So, how could I go through the structs types and output them one by one by different output functions made by me?
You should have a look at cxx-prettyprint. http://louisdx.github.com/cxx-prettyprint/
I think it does all your asking for.
This question already has answers here:
Closed 11 years ago.
Possible Duplicate:
Which is the fastest algorithm to find prime numbers?
What is the fastest way to check if a number is prime( large numbers). I have tried the standard method i.e running a loop till root(n) or (n/2) and checking if anything divides it. Also i have tried the sieve method. Is there anything better to implement in c++?
http://en.wikipedia.org/wiki/Primality_test has all you need.
One tip is that you can ignore any even numbers (so add 2 at a time when either looking for factors or checking values).