sorting - C++ how to sort vector<class *> with operator < -

i have

 class c1{  public:     int number;      c1()     {         number=rand()%10;     }      bool operator < (c1 *w)     {         return number < w->number;     }   };  vector<c1*> vec = { ... } sort(vec.begin(),vec.end())  

why dosent sort ?

but if had

 bool operator < (c1 w)     {         return number < w.number;     } 

and

vector<c1> vec = { ... } 

it have been sorted !

the straightforward approach define function

bool c1_ptr_less( c1 const *lhs, c1 const *rhs ) {     return lhs->something < rhs->something; }  std::sort( vec.begin(), vec.end(), & c1_ptr_less ); 

what suggest generic functor take care of all pointer arrays

struct pointer_less {     template< typename t >     bool operator()( t const *lhs, t const *rhs ) const         { return * lhs < * rhs; } };  std::sort( vec.begin(), vec.end(), pointer_less() ); 

armed this, define usual c1::operator< ( const c1 & ) , likewise other classes.

generally, best practice avoid pointers entirely, including arrays of pointers.