So how should I sort?

C has a library routine for sorting:
void qsort(void *, unsigned, unsigned,
int (*)(const void *, const void *));

C++ has one too, though you may have to look for it on your implementation:
template<class T> void sort(T, T);

C has a library routine for sorting: void qsort(void *, unsigned, unsigned, int (*)(const void *, const void *));