c/c++ BigInteger Implementation for calculating factorial

Question

How can i implement "Big-Integer" for c/c++ programming? Is there any build function in c/c++ library? or do I have to implement the Function for it?

{  
  BigInt fac=1;
  int value=25;
  for(int i=1;i<=25;i++){
    fac=fac*i;
  }
  cout<<fac<<endl;
}

I am trying like this but seems like there is no data type like "Big Int" .

There's no such thing like a c/c++ language. What made you think, there should be a datatype like `BigInt`? The standards don't provide one. You may lookup finding libraries supporting such though. But asking to recommend one is OT here. — πάντα ῥεῖ, Sep 05 '15 at 17:51
Programming by guessing (at datatypes and _languages_) is not usually effective :) — Lightness Races in Orbit, Sep 05 '15 at 18:32

score 1 · Answer 1 · answered Sep 05 '15 at 17:45

1

You can use boost::multiprecision::cpp_int if you need an arbitrary precision integer. If you need it to be fast, you can use boost::multiprecision with linking to one of several options of an external back-end.

answered Sep 05 '15 at 17:45

Chris Beck

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score 0 · Answer 2 · answered Sep 05 '15 at 18:14

0

Using a array to store the single integers at a time will help you achieving the desired effect! This is the one of the best tutorial from codechef for this well known big-int problems!

Hope that helps!

answered Sep 05 '15 at 18:14

Sagar Kar

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c/c++ BigInteger Implementation for calculating factorial

2 Answers2