Use a Better Algorithm and Beat Haskell Today!

Note: This refers to the article “Use those extra cores and beat C today! (Parallel Haskell redux)”, and should be viewed as a good-natured ribbing!
I’ll see your sensational headline and raise you a better algorithm!
The Code:

#include "gmpxx.h"
#include <iostream>
#include <sys/time.h>
 
using namespace std;
 
mpz_class fib(unsigned int num)
{
mpz_class a(1), b(1);
mpz_class temp;
 
while(num– > 1)
[...]

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