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Karatsuba Wrong Answer After 6 Decimal digits 15 Years Ago by Peter_APIIT …lt; second << " : " << Karatsuba(first, second); } return 0; } // ============================================= void userInput(ulong&… ) { ++lengthPower; } return lengthPower; } // ============================================= ulong Karatsuba(const ulong& first, const ulong& second) { if… Re: Karatsuba Wrong Answer After 6 Decimal digits 15 Years Ago by ArkM It seems you don't understand that no need in Karatsuba algorithm while you are trying to get unsigned long results:…you can't return unsigned long value from Karatsuba function! No need in Karatsuba algorithm if you have bigint library: there is… representation is a simple text string. Try to implement Karatsuba algorithm for this representation. [C++]Karatsuba's multiplication using stl vectors 14 Years Ago by mazix2 ….insert(i,0); return a+b; } vector<int> karatsuba(vector<int> v1,vector<int> v2…,v,w,uPLUSv,wMINUSuv,res2; u = karatsuba(x1,y1,m); v = karatsuba(x2,y2,m); w = karatsuba(X,Y,m); uPLUSv = u+v… Getting Error In Karatsuba's Multiplication Program 9 Years Ago by SK1994 …return (n1 < n2) ? n1 : n2; } int karatsuba(BigInteger a1, BigInteger b1) { int n1, n2 = 0; for…mask1; d = n2 % mask1; res1 = karatsuba(a, c); res2 = karatsuba(b, d); res3 = karatsuba(a + b, c + d); if (l… Error on Karatsuba multiplication algorithm's implementation 8 Years Ago by Gà_1 …of this function, everything work fine except Karatsuba function (I call it *kmulrun*). … result. Here is my implementation of Karatsuba algorithm plus all related function: typedef…< r ? 1 : 0; } } del0(res); } // Karatsuba multiplication functions void kmulrun(bigint &res, const bigint &… Re: Recursive multiplication and Karatsuba 13 Years Ago by Darryl.Burke …-forums.org/new-java/40500-recursive-multiplication-karatsuba.html[/url] [url]http://javaprogrammingforums.com…/algorithms-recursion/7920-recursive-multiplication-karatsuba.html[/url] [url]http://www.programmersheaven.…/mb/java/422411/422411/recursive-multiplication-and-karatsuba/[/url] [url]http://www.coderanch.com… Recursive multiplication and Karatsuba 13 Years Ago by jsp01 …) Also then how would you use this and implement a Karatsuba multiplication if say n>3. Re: Karatsuba Wrong Answer After 6 Decimal digits 15 Years Ago by ArkM Take into account that [code] 123456 * 654321 * 80779853 == 6525384681074833728 [/code] but [icode]std::numeric_limits<long>::max()[/icode] is equal to 2147483647 on 32-bit processors (integer overflow is not detected). Try [icode]long long[/icode] type (it's supported by modern compilers now), its max value is 9223372036854775807. … Re: Karatsuba Wrong Answer After 6 Decimal digits 15 Years Ago by Peter_APIIT Why will causing this value although it can fit that value ? Do you have any good big integer library ? I need those supports up to 512 bits ? Thanks Re: Karatsuba Wrong Answer After 6 Decimal digits 15 Years Ago by ArkM No, I have not bigint libraries. I have no need in these libraries. Have you ever seen the phrase "Search Google"? Try this (for [i]bigint library[/i]) and you will get lots of links, for example (from the 1st page): [url]http://mattmccutchen.net/bigint/[/url] [url]http://en.wikipedia.org/wiki/Arbitrary-precision_arithmetic[/url] [… Re: Karatsuba Wrong Answer After 6 Decimal digits 15 Years Ago by Peter_APIIT I do searching in google but i not sure which one is easy, popular. How about GNU MP ? Thanks. Re: Karatsuba Wrong Answer After 6 Decimal digits 15 Years Ago by Peter_APIIT Thanks for your help. In cases, iI don't want to create my own big int class since there are many outside. I just want some big int library which is template based, easy to use. For instance, bigInt<150> aBigInt; 150 is the number of bits. Re: [C++]Karatsuba's multiplication using stl vectors 14 Years Ago by mazix2 And, as you can see it in my code, the base is 256, not as usually 10. Re: Getting Error In Karatsuba's Multiplication Program 9 Years Ago by tinstaafl One thing I noticed is that your algorithm is using the literal value of `char` instead of offsetting it by 48 to get the integer value represented by the char. source(.s) give different output with respect to .c file 11 Years Ago by nchy13 hi all. i have implemented Karatsuba algorithm for multiplication of large numbers . when i compile .c … below the c program. Here is **ulti.c(program for karatsuba algorithm)** #include<stdio.h> #include<string.h… Re: bitwise multiplication with an array of ints 12 Years Ago by vijayan121 Karatsuba, perhaps? [url]http://en.wikipedia.org/wiki/Karatsuba_algorithm[/url] [url]http://mathforum.org/library/drmath/view/71637.html[/url] C: [url]http://ozark.hendrix.edu/~burch/proj/karat/karat.txt[/url] (read the copyright notice.) Re: Very large integer 16 Years Ago by vijayan121 …are very large. the other popular multiplication algorithms are Karatsuba and Toom-3. [url]http://gmplib.org/manual/…Multiplication-Algorithms.html#Multiplication-Algorithms[/url] in general Karatsuba is suitable for smaller numbers, Toom-3 for … limbs: 32-bits per limb on this processor) Karatsuba 18 limbs Toom-3 139 limbs FFT MODF 456… Re: multiplication large number using mpi 13 Years Ago by tyrantbrian You can use the Karatsuba Fast Multiplication algorithm for this purpose. We normally employ this … googling. It shows how MPI can be used to perform Karatsuba Multiplication Algorithm in parallel. The code appears in GnuPG as… Re: Factorial of any length 19 Years Ago by Asif_NSU … multiplication can be implemented with even faster algorithms namely 1. Karatsuba's divide-and-conquer algorithm 2. Fourier transforms 3. Chinese… Re: Newmember with big problem!!! 18 Years Ago by iamthwee … rather than multiplying. multiplying can lend itself to varying speeds - Karatsuba etc.I'd imagine addition to be constant. But I… Re: mulitplication of two huge integers 17 Years Ago by iamthwee @faiz read the following, take out what you need. [url]http://ozark.hendrix.edu/~burch/proj/karat/index.html[/url] All he seems to be doing, if you ignore the complexity of the karatsuba implementation, is returning the string reversed, putting some zeros on the end, and doing grade school multiplication. Simple stuff.