How to Declare a Stack in C++? Last Updated : 04 Mar, 2024 Comments Improve Suggest changes Like Article Like Report 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++. Declaring a Stack in C++ STLThe 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 Stackstack<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; } OutputTop 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. Comment More infoAdvertise with us Next Article How to Declare a Stack in C++? A anjalibo6rb0 Follow Improve Article Tags : C++ Programs C++ STL cpp-stack CPP Examples +1 More Practice Tags : CPPSTL Similar Reads How to Clear a Stack in C++? In C++, clearing a stack means removing all element from the stack container leaving it empty. In this article, we will learn how to clear a stack in C++.The most efficient method to clear a stack is by assigning the new empty stack to our original stack container. Let's take a look at the code exam 3 min read How to Declare a List in C++? In C++, list is a data structure used to store elements sequentially in non-contiguous memory locations. This container implements doubly linked list which contains pointers to both previous and next elements in the sequence. In this article, we will learn how to declare a list in C++. Declare a Lis 2 min read How to Copy a Stack in C++? In C++, stacks are a type of container adaptor with a 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 are going to discuss how to copy a stack in C++. Copying a Stack to Another in C++To copy a s 2 min read How to Compare Two Stacks in C++? In C++, a stack is a type of data structure where elements are inserted and removed according to the Last-In-First-Out (LIFO) principle. In this article, we will see how to compare two stacks in C++. Example: Input: stack1 = {10,20,30,40,50}stack2 = {10,20,30,40,50}Output:Stacks are equalComparing T 2 min read How to Create a Stack of Map in C++? In C++, the std::stack is a container that follows the LIFO (Last In, First Out) rule, whereas std::map is an associative container that stores key-value pairs. In this article, we will learn how to create a stack of a map in C++. Example:Input: myMap = { {1: ‘a’}, {2: ‘b’}, {3: ‘c’} }; myMap = { {4 2 min read How to Create a Stack of Set in C++? In C++ STL, 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. Sets are a type of associative container in which each element is unique and in some sorted order. In this arti 2 min read How to Declare an Array in C++? In C++, an array is a collection of similar data types in which elements are stored in contiguous memory locations. In this article, we will learn how to declare an array in C++. Declaring an Array in C++In C++, we can declare an array by specifying the type of its elements, followed by the name of 2 min read How to Create a Stack of Stack in C++? In C++, the stack is a container that follows the LIFO (Last In, First Out) order in which the elements are inserted and removed from it. In this article, we will learn how to create a stack of a stack in C++. Example:Input:Elements in stack1= 1, 2, 3, 4Elements in stack2= 5, 6, 7Output:Elements in 2 min read How to Create a Stack of Lists in C++? In C++, a list is a sequence container that allows dynamic insertion and deletion operations, whereas a stack is a data structure that follows last-in, first-out (LIFO). In this article, we will learn how to create a stack of lists in C++. Example: Input: list1 = { 1, 2, 3, 4 }list2 = { 5, 6, 7 }Out 2 min read How to Create a Stack of Queue in C++? In C++, the std::stack is a container that follows the LIFO (Last In, First Out) rule, whereas std::queue is a container that follows the FIFO (First In, First Out) rule. In this article, we will learn how to create a stack of a queue in C++. Example: Input:myQueue = { a, b, c };myQueue = { d, e };O 2 min read Like