Declaring a Stack in C++ STL
The C++ STL provides a container std::stack that implements stack data structure. To declare a stack, we can use the following syntax
Syntax to Declare a Stack
stack<dataType> stackName;
Here,
- dataType: It is the type of data that a stack will be storing.
C++ Program to Declare A Stack
C++
// C++ Program to illustrate how to declare a stack #include <iostream> #include <stack> using namespace std; // Driver Code int main() { // Declaring a stack of integers stack< int > stackData; // Pushing elements in the stack stackData.push(10); stackData.push(20); stackData.push(30); // Printing the top element cout << "Top element of the stack is: " << stackData.top() << endl; // Removing elements from the stack stackData.pop(); // Check if the stack is empty if (stackData.empty()) { cout << "The stack is empty." << endl; } else { cout << "The stack is not empty." << endl; } // Printing Size of the stack cout << "Size of the stack: " << stackData.size() << endl; return 0; } |
Top element of the stack is: 30 The stack is not empty. Size of the stack: 2
Time Complexity: O(N)
Auxiliary Space: O(N), where N is the number of stack elements.
How to Declare a Stack in C++?
In C++, Stacks are a type of container adaptor with LIFO(Last In First Out) type of working, where a new element is added at one end (top) and an element is removed from that end only. In this article, we will learn how to declare a stack in C++.