operator< (<stack>)

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

bool operator<(
   const stack <Type, Container>& _Left,
   const stack <Type, Container>& _Right
);

Parameters

  • _Left
    An object of type stack.

  • _Right
    An object of type stack.

Return Value

true if the stack on the left side of the operator is less than and not equal to the stack on the right side of the operator; otherwise false.

Remarks

The comparison between stack objects is based on a pairwise comparison of their elements. The less-than relationship between two stack objects is based on a comparison of the first pair of unequal elements.

Example

// stack_op_lt.cpp
// compile with: /EHsc
#include <stack>
#include <list>
#include <iostream>

int main( )
{
   using namespace std;

   // Declares stacks with list base container
   stack <int, list<int> > s1, s2, s3;

   s1.push( 2 );
   s1.push( 4 );
   s1.push( 6 );
   s1.push( 8 );
   s2.push( 5 );
   s2.push( 10 );
   s3.push( 2 );
   s3.push( 4 );
   s3.push( 6 );
   s3.push( 8 );

   if ( s1 >= s2 )
      cout << "The stack s1 is greater than or equal to "
           << "the stack s2." << endl;
   else
      cout << "The stack s1 is less than "
           << "the stack s2." << endl;

   if ( s1>= s3 )
      cout << "The stack s1 is greater than or equal to "
           << "the stack s3." << endl;
   else
      cout << "The stack s1 is less than "
           << "the stack s3." << endl;

   // to print out the stack s1 ( by unstacking the elements):
   stack <int>::size_type i_size_s1 = s1.size( );
   cout << "The stack s1 from the top down is: ( ";
   unsigned int i;
   for ( i = 1 ; i <= i_size_s1 ; i++ )
   {
      cout << s1.top( ) << " ";
      s1.pop( );
   }
   cout << ")." << endl;
}

The stack s1 is less than the stack s2.
The stack s1 is greater than or equal to the stack s3.
The stack s1 from the top down is: ( 8 6 4 2 ).

Requirements

Header: <stack>

Namespace: std

See Also

Concepts

<stack> Members

Standard Template Library