std::stack::top

 

C++

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Technical Specifications

 

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array (C++11)

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std::stack

Member functions

stack::stack

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Element access

stack::top

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stack::emplace

stack::pop

stack::swap

 

reference top();
const_reference top() const;

Returns reference to the top element in the stack. This is the most recently pushed element. This element will be removed on a call to pop(). Effectively calls c.back().

Parameters

(none)

Return value

Reference to the last element

Complexity

Constant

Example

Run this code

#include <stack>
#include <iostream>
 
int main()
{
    std::stack<int>   s;
 
    s.push( 2 );
    s.push( 6 );
    s.push( 51 );
 
    std::cout << s.size() << " elements on stack\n";
    std::cout << "Top element: "
	      << s.top()         // Leaves element on stack
	      << "\n";
    std::cout << s.size() << " elements on stack\n";
    s.pop();
    std::cout << s.size() << " elements on stack\n";
    std::cout << "Top element: " << s.top() << "\n";
 
    return 0;
}

Output:

3 elements on stack
Top element: 51
3 elements on stack
2 elements on stack
Top element: 6

See also

push	inserts element at the top (public member function)
pop	removes the top element (public member function)