EC_Group::load_EC_group_info(const char* p_str,
                             const char* a_str,
                             const char* b_str,
                             const char* g_x_str,
                             const char* g_y_str,
                             const char* order_str,
                             const OID& oid)
   {
   const BigInt p(p_str);
   const BigInt a(a_str);
   const BigInt b(b_str);
   const BigInt g_x(g_x_str);
   const BigInt g_y(g_y_str);
   const BigInt order(order_str);
   const BigInt cofactor(1); // implicit

   return std::make_shared<EC_Group_Data>(p, a, b, g_x, g_y, order, cofactor, oid);
   }
EC_Group::load_EC_group_info(const char* p_str,
                             const char* a_str,
                             const char* b_str,
                             const char* g_x_str,
                             const char* g_y_str,
                             const char* order_str,
                             const OID& oid)
   {
   const BigInt p(p_str);
   const BigInt a(a_str);
   const BigInt b(b_str);
   const BigInt g_x(g_x_str);
   const BigInt g_y(g_y_str);
   const BigInt order(order_str);
   const BigInt cofactor(1);  

   return std::make_shared<EC_Group_Data>(p, a, b, g_x, g_y, order, cofactor, oid);
   }