factors.cpp File Reference

#include <chrono>
#include <cmath>
#include <iostream>
#include <openGPMP/core/threads.hpp>
#include <openGPMP/nt/factorization.hpp>
#include <vector>

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Functions
int	main ()

Function Documentation

main()

int main

(

void

)

Examples

factors.cpp.

Definition at line 15 of file factors.cpp.

           {
    gpmp::Factorization factorization;
 
    // find prime factor of 123456789
    int64_t n = 9223372036854775803;
    int64_t factor = factorization.pollard_rho(n);
 
    // print the result
    std::cout << "The smallest prime factor of " << n << " is " << factor
              << std::endl;
 
    /******* EXAMPLE USING openGPMP's THREADPOOL *******/
    //
    // specify the numbers to factorize
    // pollard_rho accepts 64 bit integers
    // std::vector<int64_t> nums_to_factorize = {
    //    9223372036854775803, 9223372036854775807, 9223372036854775303,
    //    4567890123456789LL,  5678901234567890LL,  6789012345678901LL,
    //    7890123456789012LL,  8901234567890123LL};
    std::vector<uint64_t> nums_to_factorize = {
        9223372036854775803,   9223372036854775807,   9223372036854775303,
        4567890123456789LL,    5678901234567890LL,    6789012345678901LL,
        7890123456789012LL,    8901234567890123LL,    9999999967LL,
        12345678901234567LL,   987654321987654321LL,  2147483647LL,
        9223372036854775783LL, 1311768467463790320LL, 7237005577332262210LL,
        3037000499LL,          2305843009213693951LL, 2305843009213693967LL,
        2305843009213693971LL, 2305843009213693973LL, 2305843009213693977LL,
        2305843009213693989LL};
 
    // std::vector<std::future<int64_t>> results =
    //    factorization.pollard_rho_thread(nums_to_factorize);
 
    //    for (auto &res : results) {
    //        std::cout << res.get() << std::endl;
    //    }
 
    std::vector<std::future<uint64_t>> results;
    gpmp::core::ThreadPool *pool = new gpmp::core::ThreadPool(2);
    gpmp::Factorization factors;
    for (const auto &num : nums_to_factorize) {
        results.emplace_back(gpmp::core::ThreadDispatch().dispatch(
            *pool,
            &gpmp::Factorization::pollard_rho,
            &factors,
            num));
    }
 
    for (auto &res : results) {
        std::cout << res.get() << std::endl;
    }
 
    delete pool;
 
    return 0;
}

References gpmp::Factorization::pollard_rho(), and python.linalg::res.