mul_ttmath.cpp

#include "ttmath/ttmath.h"
#include <ctime>
#include <iostream>
#include <cstdlib>
#include <string>


#define DIGITS 200
#define TESTS  100000
#define TTMATH_MANTISSA_SIZE_BITS 1344
// because 2^1344 = 3.839...e+404  (1344 = 21 * 64)
// and we need more than 400 digits after comma
// (multiplication needs at least DIGITS * 2 to store all the digits)


char rand_digit()
{
    return '0' + int(double(std::rand()) / RAND_MAX * 9.0);
}


void generate_something(std::string & out)
{
    out.resize(DIGITS);

    for(size_t i=0 ; i<DIGITS ; ++i)
        out[i] = rand_digit();
}


int main()
{
std::srand(time(0));
ttmath::Big<1, TTMATH_BITS(TTMATH_MANTISSA_SIZE_BITS)> a,b,c;
int i, i2;
std::string str_a, str_b;

    clock_t t1 = clock();

    for(i=0 ; i<10 ; ++i)
    {
        generate_something(str_a);
        generate_something(str_b);

        a = str_a;
        b = str_b;

        //std::cout << str_a << std::endl;
        //std::cout << str_b << std::endl;

        for(i2 = 0 ; i2<TESTS ; ++i2)
            c = a * b;
    }

    clock_t t2 = clock();

    std::cout << "time: " << (t2-t1) << std::endl;
}