C++/List/list erase

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Demonstrating the STL list erase function

  
 
#include <iostream>
#include <cassert>
#include <list>
#include <string>
#include <algorithm>
using namespace std;

int main()
{
  string s("remembering");
  list<char> list1(s.begin(), s.end());
  list<char>::iterator j;
  j = find(list1.begin(), list1.end(), "i");
  list1.erase(j++);
  list<char>::iterator i;
  for (i = list1.begin(); i != list1.end(); ++i)
    cout << *i << " ";
  list1.erase(j++);
  for (i = list1.begin(); i != list1.end(); ++i)
    cout << *i << " ";
  list1.erase(j++);
  for (i = list1.begin(); i != list1.end(); ++i)
    cout << *i << " ";
  list1.erase(list1.begin());
  for (i = list1.begin(); i != list1.end(); ++i)
    cout << *i << " ";

  list1.erase(list1.begin());
  for (i = list1.begin(); i != list1.end(); ++i)
    cout << *i << " ";
  return 0;
}
 /* 
r e m e m b e r n g

r e m e m b e r g

r e m e m b e r

e m e m b e r

m e m b e r

 */


keep only the top 3 salespeople

  
#include <algorithm>
#include <functional>
#include <iostream>
#include <iterator>
#include <list>
using namespace std;
class Employee
{
   public:
   Employee( const string& name = "", int sales = 0,int district = 0 );
   bool operator>( const Employee& rhs ) const;
   void print() const;
   private:
   int district_;
   string name_;
   int sales_;
};
inline
Employee::Employee( const string& name, int sales,
   int district )
   : district_( district ), name_( name ), sales_( sales )
{} 
inline
bool Employee::operator>( const Employee& rhs ) const
{ return sales_ > rhs.sales_; }
inline
void Employee::print() const
{ cout << name_ << " from District " << district_
   << " has sales of $" << sales_ << endl;
}
int main( )
{
   list<Employee> list1;
   list1.push_back( Employee( "A", 3, 1 ) );
   list1.push_back( Employee( "B", 4, 1 ) );
   list1.push_back( Employee( "C", 8, 1 ) );
   list1.sort( greater<Employee>() );
   for_each( list1.begin(), list1.end(), mem_fun_ref( &Employee::print ) );
   const int top_positions = 3;
   list<Employee>::iterator position = list1.begin();
   advance( position, top_positions );
   list1.erase( position, list1.end() );
   for_each( list1.begin(), list1.end(),mem_fun_ref( &Employee::print ) );
}