Stack in C++ STL - GeeksforGeeks

Stacks are a type of container adaptors with LIFO(Last In First Out) type of working, where a new element is added at one end and (top) an element is removed from that end only.

The functions associated with stack are:
empty() – Returns whether the stack is empty – Time Complexity : O(1)
size() – Returns the size of the stack – Time Complexity : O(1)
top() – Returns a reference to the top most element of the stack – Time Complexity : O(1)
push(g) – Adds the element ‘g’ at the top of the stack – Time Complexity : O(1)
pop() – Deletes the top most element of the stack – Time Complexity : O(1)

// CPP program to demonstrate working of STL stack 
#include <bits/stdc++.h> 
using namespace std; 
  
void showstack(stack <int> s) 
{ 
    while (!s.empty()) 
    { 
        cout << '\t' << s.top(); 
        s.pop(); 
    } 
    cout << '\n'; 
} 
  
int main () 
{ 
    stack <int> s; 
    s.push(10); 
    s.push(30); 
    s.push(20); 
    s.push(5); 
    s.push(1); 
  
    cout << "The stack is : "; 
    showstack(s); 
  
    cout << "\ns.size() : " << s.size(); 
    cout << "\ns.top() : " << s.top(); 
  
  
    cout << "\ns.pop() : "; 
    s.pop(); 
    showstack(s); 
  
    return 0; 
} 

Output:

The stack is :     1    5    20    30    10

s.size() : 5
s.top() : 1
s.pop() :     5    20    30    10

List of functions of Stack:

Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above

Rated as one of the most sought after skills in the industry, own the basics of coding with our C++ STL Course and master the very concepts by intense problem-solving.

My Personal Notes

Recommended Posts: