c - C unsigned long long 在数组中的另一个溢出

Question

假设我有一个数组unsigned long long，有没有办法将溢出放在下一个ull？我想要确切的数字，所以不能选择加倍。现在这就是我所拥有的：

#include <stdio.h>

unsigned long long d[2] = {1,0}, n[2] = {0,0}; // denominator, numerator
unsigned long long nd = 1;

int main(int argc,char* argv[])
{
    while(1){

        if(nd+2 < nd) // next denominator greater than 2^64-1
            return 0;
        // n = n*nd + d
        n[0] = n[0] * nd + d[0];
        // n[1] += *overflow    <------
        n[1] = n[1] * nd + d[1];
        d[0] *= nd;
        // d[1] += *overflow    <------
        d[1] *= nd;
        printf("current denominator: %llu -> 4*%llu/%llu\n", nd, n, d);
        nd += 2; //increment next denominator
    }
}