Hi i would like to know how to make program options play nicely with tuple. int main( int ac, char* av[] ) { namespace po = boost::program_options; po::options_description desc("Allowed options"); std::vector<BigInteger> key_pair; desc.add_options() ("generate", "generates a pair of key") ("secert", po::value(&key_pair)->multitoken(), "creates the share secret key"); po::variables_map vm; po::store(po::parse_command_line(ac, av, desc), vm); po::notify(vm); try { if (vm.count("generate")) { BigInteger my_prime = encryptcpw::random_prime<BigInteger>(&algocpw::Solovay_Stressen<BigInteger>, 16); std::cout << "my prime: " << my_prime << "\n"; boost::tuple pare(encryptcpw::dh_init<BigInteger>( my_prime )); std::cout << "pair of generated number: " << pare << "\n"; } if (vm.count("secert")) { const BigInteger p( encryptcpw::random_prime<BigInteger>(&algocpw::Solovay_Stressen<BigInteger>, 16)); std::cout << encryptcpw::dh_secret<BigInteger>( p, key_pair[0], key_pair[1]); } } catch (const char* error) { std::cerr << error << "\n"; } } I would like to replace vector with tuple. boost::tuple key_pair; for some reason doing that cause the program to crash.. when run DiffieHellman --generate 1371 2397