Big numbers library in c++
I'm doing a project which requires really big numbers, up to 100 digits. I have read that java supports big integers (java.Math.BigInteger), and I want to know if there is something like that in C++. So, here is my question: Is there a standard or non-standard c++ library which implements big integers?
Note: If there is no standard implementation for big integers, I would like a simple non-standard. Thanks in advance.
Answer
The GNU Multiple Precision Arithmetic Library does what you want http://gmplib.org/
Gnu MP is a C library but it has a C++ class Interface and if you are interested only in big integers, you may just deal with mpz_class. Look at the sample below which I took from the page C++ Interface General
int main (void)
{
mpz_class a, b, c;
a = 1234;
b = "-5678";
c = a+b;
cout << "sum is " << c << "\n";
cout << "absolute value is " << abs(c) << "\n";
return 0;
}