public static void Swap(this PeopleByAge p, nint i, nint j) { var tmp = p[i]; p[i] = p[j]; p[j] = tmp; }
public static bool Less(this PeopleByAge p, nint i, nint j) { return(p[i].Age < p[j].Age); }
public static nint Len(this PeopleByAge p) { return(len(p)); }
public static void Swap(this PeopleByAge p, nint i, nint j) { (p[i], p[j]) = (p[j], p[i]); }