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greater Struct

A binary predicate that tests whether a value of a specified type is greater than another value of that type.

template<class Type>
   struct greater : public binary_function <Type, Type, bool> 
   {
      bool operator()(
         const Type& _Left, 
         const Type& _Right
      ) const;
   };

Parameters

  • _Left
    The left operand of type Type in the inequality to be tested.

  • _Right
    The right operand of type Type in the inequality to be tested.

Return Value

true if _Left > _Right; false if _Left <= _Right.

Remarks

The binary predicate greater<Type> provides a strict weak ordering of a set of element values of type Type into equivalence classes if and only if this Type satisfies the standard mathematical requirements for being so ordered. The specializations for any pointer type yield a total ordering of elements in that all elements of distinct values are ordered with respect to each other.

Example

// functional_greater.cpp
// compile with: /EHsc
#include <vector>
#include <algorithm>
#include <functional>
#include <cstdlib>
#include <iostream>

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

   int i;
   for ( i = 0 ; i < 8 ; i++ )
   {
      v1.push_back( rand( ) );
   }

   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<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, 
   // specify binary predicate greater<int>( )
   sort( v1.begin( ), v1.end( ), greater<int>( ) );
   cout << "Resorted vector v1 = ( " ;
   for ( Iter1 = v1.begin( ) ; Iter1 != v1.end( ) ; Iter1++ )
      cout << *Iter1 << " ";
   cout << ")" << endl;
}

Output

Original vector v1 = ( 41 18467 6334 26500 19169 15724 11478 29358 )
Sorted vector v1 = ( 41 6334 11478 15724 18467 19169 26500 29358 )
Resorted vector v1 = ( 29358 26500 19169 18467 15724 11478 6334 41 )

Requirements

Header: <functional>

Namespace: std

See Also

Reference

Standard Template Library

Other Resources

<functional> Members