Stack Data Structure Last Updated : 07 Jul, 2025 Summarize Comments Improve Suggest changes Share Like Article Like Report A Stack is a linear data structure that follows a particular order in which the operations are performed. The order may be LIFO(Last In First Out) or FILO(First In Last Out). LIFO implies that the element that is inserted last, comes out first and FILO implies that the element that is inserted first, comes out last.It behaves like a stack of plates, where the last plate added is the first one to be removed. Think of it this way:Pushing an element onto the stack is like adding a new plate on top.Popping an element removes the top plate from the stack.Basics Introduction to StackStack Array ImplementationStack Linked List Implementation Stack Implementation using DequeApplications of StackImplementations in Different LanguagesStack in C++ STLStack in JavaStack in PythonStack in C#Stack in JavaScriptEasy Problems The Celebrity ProblemQueue using StacksTwo stacks in an arrayStack using QueuesStack using priority queue Stack using single queueInfix to PostfixPrefix to InfixPrefix to PostfixPostfix to PrefixPostfix to InfixInfix To Prefix Check for balanced parenthesesArithmetic Expression EvalutionEvaluation of Postfix ExpressionReverse a stack using recursionReverse WordsReverse a string using stackReversing a QueueReversing the first K of a QueueA DS with O(1) OperationsMedium Problems k Stacks in an ArrayMergable StackPrevious Smaller ElementNext Greater Element Stock Span Problem Buildings Facing SunNext Smaller of next GreaterNext Greater Frequency ElementMax product of indexes of greater on left and rightIterative Tower of HanoiSort a StackReverse a StackDelete middle of a stackCheck for queue sortableCheck for stack sortable Index of closing bracket for a given opening bracketMax Diff between nearest left and right smallerDelete consecutive same wordsHard ProblemsLargest Rectangular Area in a Histogram Sum of Max of all SubarraysMax of Mins of every window sizeStack that supports getMin() Stack with max frequencyLongest valid substring Check Redundant BracketStack Permutations Remove brackets containing + and – operators Quick Links :‘Practice Problems’ on Stack‘Videos’ on Stack‘Quizzes’ on StackRecommended:Learn Data Structure and Algorithms | DSA TutorialStack in Scala Comment More infoAdvertise with us Next Article Queue Data Structure H harendrakumar123 Follow Improve Article Tags : Stack DSA Practice Tags : Stack Similar Reads DSA Tutorial - Learn Data Structures and Algorithms DSA (Data Structures and Algorithms) is the study of organizing data efficiently using data structures like arrays, stacks, and trees, paired with step-by-step procedures (or algorithms) to solve problems effectively. Data structures manage how data is stored and accessed, while algorithms focus on 7 min read Basics & PrerequisitesTime Complexity and Space ComplexityMany times there are more than one ways to solve a problem with different algorithms and we need a way to compare multiple ways. Also, there are situations where we would like to know how much time and resources an algorithm might take when implemented. To measure performance of algorithms, we typic 13 min read Types of Asymptotic Notations in Complexity Analysis of AlgorithmsWe have discussed Asymptotic Analysis, and Worst, Average, and Best Cases of Algorithms. The main idea of asymptotic analysis is to have a measure of the efficiency of algorithms that don't depend on machine-specific constants and don't require algorithms to be implemented and time taken by programs 8 min read Data StructuresGetting Started with Array Data StructureArray is a collection of items of the same variable type that are stored at contiguous memory locations. It is one of the most popular and simple data structures used in programming. Basic terminologies of ArrayArray Index: In an array, elements are identified by their indexes. Array index starts fr 14 min read String in Data StructureA string is a sequence of characters. The following facts make string an interesting data structure.Small set of elements. Unlike normal array, strings typically have smaller set of items. For example, lowercase English alphabet has only 26 characters. ASCII has only 256 characters.Strings are immut 3 min read Hashing in Data StructureHashing is a technique used in data structures that efficiently stores and retrieves data in a way that allows for quick access. Hashing involves mapping data to a specific index in a hash table (an array of items) using a hash function. It enables fast retrieval of information based on its key. The 2 min read Linked List Data StructureA linked list is a fundamental data structure in computer science. It mainly allows efficient insertion and deletion operations compared to arrays. Like arrays, it is also used to implement other data structures like stack, queue and deque. Here’s the comparison of Linked List vs Arrays Linked List: 3 min read Stack Data StructureA Stack is a linear data structure that follows a particular order in which the operations are performed. The order may be LIFO(Last In First Out) or FILO(First In Last Out). LIFO implies that the element that is inserted last, comes out first and FILO implies that the element that is inserted first 2 min read Queue Data StructureA Queue Data Structure is a fundamental concept in computer science used for storing and managing data in a specific order. It follows the principle of "First in, First out" (FIFO), where the first element added to the queue is the first one to be removed. It is used as a buffer in computer systems 2 min read Tree Data StructureTree Data Structure is a non-linear data structure in which a collection of elements known as nodes are connected to each other via edges such that there exists exactly one path between any two nodes. Types of TreeBinary Tree : Every node has at most two childrenTernary Tree : Every node has at most 4 min read Graph Data StructureGraph Data Structure is a collection of nodes connected by edges. It's used to represent relationships between different entities. If you are looking for topic-wise list of problems on different topics like DFS, BFS, Topological Sort, Shortest Path, etc., please refer to Graph Algorithms. Basics of 3 min read Trie Data StructureThe Trie data structure is a tree-like structure used for storing a dynamic set of strings. It allows for efficient retrieval and storage of keys, making it highly effective in handling large datasets. Trie supports operations such as insertion, search, deletion of keys, and prefix searches. In this 15+ min read AlgorithmsSearching AlgorithmsSearching algorithms are essential tools in computer science used to locate specific items within a collection of data. In this tutorial, we are mainly going to focus upon searching in an array. When we search an item in an array, there are two most common algorithms used based on the type of input 3 min read Sorting AlgorithmsA Sorting Algorithm is used to rearrange a given array or list of elements in an order. 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From basic lines and angles to complex structures, it helps us understand the world around us.Geometry for Students and BeginnersThis section covers key br 2 min read Interview PreparationInterview Corner: All Resources To Crack Any Tech InterviewThis article serves as your one-stop guide to interview preparation, designed to help you succeed across different experience levels and company expectations. Here is what you should expect in a Tech Interview, please remember the following points:Tech Interview Preparation does not have any fixed s 4 min read GfG160 - 160 Days of Problem SolvingAre you preparing for technical interviews and would like to be well-structured to improve your problem-solving skills? Well, we have good news for you! GeeksforGeeks proudly presents GfG160, a 160-day coding challenge starting on 15th November 2024. 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