在 C++ 中处理任意长度的整数

p.s. Using this simple rules to work with integers and this library i computed fibonacci numbers up to the 100.000th number with a simple program (that took like 3min to code) in 15 to 20 seconds and the number occupied like 3 pages so besides being a practical library once you get to know how it works (that you had virtually no help before, some samples of the ttmath website are pretty misleading, but now you do have some help) it also seems pretty efficient, i confirmed that the 100.000th number is probably right because i increased the size (the "n") from 10000 to 50000 and the number retained the size and the initial and final digits were the same. This is the source code i used, i used a VERY BIG number for the integer size just to test, i didn't actually bothered to see on what lenght the program would start do do stuff wrong but i know that the lenght of up to the 10.000th fibonacci number won't surpass the lenght that i defined because before this i made the program 'cout' every result until it got to 10.000th and it was always growing. I also checked the first numbers of the sequence before when i paused the program and i was seeing the 'digits grow' and confirmed the first fibonacci numbers of the sequence and they were correct. NOTE: This source code will only display the number of the fibonacci sequence that you want to know, it will only show you the numbers "growing" if you uncomment the commented lines.

#define TTMATH_DONT_USE_WCHAR
#include <ttmath/ttmath.h>
#include <iostream>

using namespace std;
int main () {

int fibonaccinumber;
cin >> fibonaccinumber;
cin.ignore();

ttmath::UInt<10000> fibonacci1,fibonacci2,fibonacci3;
fibonacci1 = 1;
fibonacci2 = 1;
//cout << "1. " << fibonacci1 << "
2. " << fibonacci2 << "
";

for(int i=3;i<=fibonaccinumber;i++)
{fibonacci3 = fibonacci1 + fibonacci2;
//   cout << i << ". " << fibonacci3 << "
";
fibonacci1=fibonacci2;
fibonacci2=fibonacci3;}

cout << "the " << fibonaccinumber << "th fibonacci number is " << fibonacci2;

string endprog;
getline(cin,endprog);
return 0;}  

我还没有修改这个图书馆的任意精度浮点数，但是当我这样做时，如果我看到人们对此指南感兴趣，我将继续扩展本指南，感谢所有评论和回答.