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operator< (<iterator>)

Tests if the iterator object on the left side of the operator is less than the iterator object on the right side.

template<class RandomIterator>
   bool operator<(
      const reverse_iterator<RandomIterator>& _Left,
      const reverse_iterator<RandomIterator>& _Right
   );

Parameters

  • _Left
    An object of type iterator.

  • _Right
    An object of type iterator.

Return Value

true if the iterator on the left side of the expression is less than the iterator on the right side of the expression; false if it is greater than or equal to the iterator on the right.

Remarks

One iterator object is less than another if it addresses an element that occurs earlier in the container than the element addressed by the other iterator object. One iterator object is not less than another if it addresses either the same element as the other iterator object or an element that occurs later in the container than the element addressed by the other iterator object.

Example

// iterator_op_lt.cpp
// compile with: /EHsc
#include <iterator>
#include <vector>
#include <iostream>

int main( )
{
   using namespace std;
   int i;

   vector<int> vec;
   for ( i = 0 ; i < 6 ; ++i )
   {
      vec.push_back ( 2 * i );
   }
   
   vector <int>::iterator vIter;

   cout << "The initial vector vec is: ( ";
   for ( vIter = vec.begin( ) ; vIter != vec.end( ); vIter++)
      cout << *vIter << " ";
   cout << ")." << endl;

   // Initializing reverse_iterators to the last element
   vector <int>::reverse_iterator rVPOS1 = vec.rbegin ( ), 
           rVPOS2 = vec.rbegin ( );
   
   cout << "The iterators rVPOS1& rVPOS2 initially point to the "
           << "first element\n in the reversed sequence: "
           << *rVPOS1 << "." << endl;

   if ( rVPOS1 < rVPOS2 )
      cout << "The iterator rVPOS1 is less than"
              << " the iterator rVPOS2." << endl;
   else
      cout << "The iterator rVPOS1 is not less than"
              << " the iterator rVPOS2." << endl;

   rVPOS2++;
   cout << "The iterator rVPOS2 now points to the second "
           << "element\n in the reversed sequence: "
           << *rVPOS2 << "." << endl;

   if ( rVPOS1 < rVPOS2 )
      cout << "The iterator rVPOS1 is less than"
              << " the iterator rVPOS2." << endl;
   else
      cout << "The iterator rVPOS1 is not less than"
              << " the iterator rVPOS2." << endl;
}
The initial vector vec is: ( 0 2 4 6 8 10 ).
The iterators rVPOS1& rVPOS2 initially point to the first element
 in the reversed sequence: 10.
The iterator rVPOS1 is not less than the iterator rVPOS2.
The iterator rVPOS2 now points to the second element
 in the reversed sequence: 8.
The iterator rVPOS1 is less than the iterator rVPOS2.

Requirements

Header: <iterator>

Namespace: std

See Also

Reference

Standard Template Library

Other Resources

<iterator> Members