//sortVec3.cpp  --- sorting vector again,  with Comparator
//@CopyLeft by tsaiwn@csie.nctu.edu.tw
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

bool compare (int i,int j) { cout << " ha "; return (i<j); }
bool comp222(int i,int j) { cout << " C "; return (i>j); } //Descending
 // the following defines a Comparator class "Sorter"
typedef class { public:  // struct default public: but class def private
  bool operator( ) (int i,int j) { cout << " S "; return (i<j);}
} Sorter;    // this is a Comparator
Sorter myObject;    // this is a Comparator Object

template<class T> void printV(vector<T> aVt) {
  typename vector<T>::iterator it;   // used to print out content
  cout << "\n Vector contains:";
  for (it=aVt.begin(); it!=aVt.end(); ++it) cout << " " << *it;
  cout<< "\n front, back == "<< aVt.front( )<<", "<< aVt.back( )<<endl;
}// printV(

int main ( ) {
  int myints[ ] = {32,71,12,45,26,80,53,33};
  vector<int> myvector(myints, 
                   myints+(sizeof myints/sizeof myints[0]));   
  printV(myvector);
  //sort(myvector.begin( ), myvector.end( )); // use operator<
  sort(myvector.begin( ), myvector.begin( )+4); 
         // sort only first 4 items     //(12 32 45 71)26 80 53 33
  printV(myvector);
  // using compare function to sort    // 12 32 45 71(26 33 53 80)
  sort(myvector.begin()+4, myvector.end(), compare); 
  printV(myvector);
  // using an Object as comparator       //(12 26 32 33 45 53 71 80)
  sort(myvector.begin(), myvector.end(), myObject); 
  printV(myvector);
  cout << "Now sort all data with function comp222( ) ...";
  sort(myvector.begin( ), myvector.end( ), comp222); 
  printV(myvector);  
  double y[ ]={3.8, 4.9, 2.5, 40, 55};
  vector<double> vd(y, y+3);  // 3 elements
  cout << " vector<double> vd: "; printV(vd);
  return 0;
}//main(
/******
C:\testc\STL>g++ sortVec3.cpp

C:\testc\STL>a

 Vector contains: 32 71 12 45 26 80 53 33
 front, back == 32, 33

 Vector contains: 12 32 45 71 26 80 53 33
 front, back == 12, 33
 ha  ha  ha  ha  ha  ha  ha  ha  ha
 Vector contains: 12 32 45 71 26 33 53 80
 front, back == 12, 80
 S  S  S  S  S  S  S  S  S  S  S  S  S  S  S  S  S  S  S  S
 Vector contains: 12 26 32 33 45 53 71 80
 front, back == 12, 80
Now sort all data with function comp222( ) ... C  C  C  C  C  C  C
 Vector contains: 80 71 53 45 33 32 26 12
 front, back == 80, 12
 vector<double> vd:
 Vector contains: 3.8 4.9 2.5
 front, back == 3.8, 2.5
**********************/