public member function

std::stack::top

<stack>
      value_type& top ( );
const value_type& top ( ) const;
Access next element
Returns a reference to the next element in the stack. Since stacks are last-in first-out containers this is also the last element pushed into the stack.

This member function effectively calls the member function back of the underlying container object.

Parameters

none

Return value

A reference to the next element in the stack.

Member type value_type is defined to the type of value contained by the underlying container, which shall be the same as the first template parameter (T).

Example

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// stack::top
#include <iostream>
#include <stack>
using namespace std;

int main ()
{
  stack<int> mystack;

  mystack.push(10);
  mystack.push(20);

  mystack.top() -= 5;

  cout << "mystack.top() is now " << mystack.top() << endl;

  return 0;
}


Output:
mystack.top() is now 15

Complexity

Constant.

See also

stack::pop
Remove element (public member function)
stack::push
Add element (public member function)