simple_random_functions

std::default_random_engine & global_urng( )
{
static std::default_random_engine u{};
return u;
}
void randomize( )
{
    static std::random_device rd{};
    global_urng().seed( rd() );
}
int pick( int from, int thru )
{
static std::uniform_int_distribution<> d{};
 using parm_t = decltype(d)::param_type;
 return d( global_urng(), parm_t{from, thru} );
}
double pick( double from, double upto )
{
 static std::uniform_real_distribution<> d{};
 using parm_t = decltype(d)::param_type;
 return d( global_urng(), parm_t{from, upto} );
 }