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Kelas binary_negate

Templat kelas yang menyediakan fungsi anggota yang meniadakan nilai pengembalian fungsi biner tertentu. Tidak digunakan lagi di C++17 demi not_fn.

Sintaks

template <class Operation>
class binary_negate
    : public binaryFunction <typename Operation::first_argument_type,
                              typename Operation::second_argument_type, bool>
{
    explicit binary_negate(const Operation& Func);
    bool operator()(const typename Operation::first_argument_type& left,
                    const typename Operation::second_argument_type& right) const;
};

Parameter

Func
Fungsi biner yang akan dinegasikan.

left
Operan kiri fungsi biner yang akan dinegasikan.

right
Operand kanan fungsi biner yang akan dinegasikan.

Tampilkan Nilai

Negasi fungsi biner.

Keterangan

Templat kelas menyimpan salinan objek fungsi biner Func. Ini mendefinisikan fungsi operator() anggotanya sebagai mengembalikan !Func(left, right).

Konstruktor binary_negate jarang digunakan secara langsung. Fungsi pembantu not2 biasanya lebih disukai untuk mendeklarasikan dan menggunakan predikat adaptor binary_negator .

Contoh

// functional_binary_negate.cpp
// compile with: /EHsc
#define _CRT_RAND_S
#include <stdlib.h>

#include <vector>
#include <algorithm>
#include <functional>
#include <iostream>

int main( )
{
   using namespace std;
   vector <unsigned int> v1;
   vector <unsigned int>::iterator Iter1;

   unsigned int i;
   v1.push_back( 6262 );
   v1.push_back( 6262 );
   unsigned int randVal = 0;
   for ( i = 0 ; i < 5 ; i++ )
   {
      rand_s(&randVal);
      v1.push_back( randVal );
   }

   cout << "Original vector v1 = ( " ;
   for ( Iter1 = v1.begin( ) ; Iter1 != v1.end( ) ; Iter1++ )
      cout << *Iter1 << " ";
   cout << ")" << endl;

   // To sort in ascending order,
   // use default binary predicate less<unsigned int>( )
   sort( v1.begin( ), v1.end( ) );
   cout << "Sorted vector v1 = ( " ;
   for ( Iter1 = v1.begin( ) ; Iter1 != v1.end( ) ; Iter1++ )
      cout << *Iter1 << " ";
   cout << ")" << endl;

   // To sort in descending order,
   // use the binary_negate function
   sort( v1.begin( ), v1.end( ),
   binary_negate<less<unsigned int> >(less<unsigned int>( ) ) );

   // The helper function not2 could also have been used
   // in the above line and is usually preferred for convenience
   // sort( v1.begin( ), v1.end( ), not2(less<unsigned int>( ) ) );

   cout << "Resorted vector v1 = ( " ;
   for ( Iter1 = v1.begin( ) ; Iter1 != v1.end( ) ; Iter1++ )
      cout << *Iter1 << " ";
   cout << ")" << endl;
}
Original vector v1 = ( 6262 6262 2233879413 2621500314 580942933 3715465425 3739828298 )
Sorted vector v1 = ( 6262 6262 580942933 2233879413 2621500314 3715465425 3739828298 )
Resorted vector v1 = ( 3739828298 3715465425 2621500314 2233879413 580942933 6262 6262 )