A stack is a last in, first out (LIFO) abstract data type and data structure. Perhaps the most common use of stacks is to store subroutine arguments and return addresses.

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Calculating a string using stacks, Not getting the right answer [on hold]

If someone doesn't mind could they take a look at my code? For some reason, I keep getting the wrong answer when the logic seems fine to me. Mainly the solve is what is probably wrong, but if needed I ...
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46 views

Mergesorting a stack in Java

I have this small program for sorting a stack using mergesort. Basically, the aim was to use as little aid from JDK library as possible. See what I have: StackMergesort.java: ...
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55 views

Sort a stack in descending order

Maintain current element as the top element in the input stack. Pop all the elements on the ordered stack which are greater than the current element and push them in to the input stack and maintain a ...
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Stack based esoteric language interpreter in Ruby

For a while now, I've wanted to write a stack-based "Turing-tarpit". This is the perfect excuse to learn Ruby, which I have never used before, so I wrote Brain-flak. The language only uses these ...
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36 views

Three stacks in a single array

I have implemented three stacks in a single array in Java. Any advice on object oriented design, coding structure, logical part or any sort of advice would be appreciated. ...
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2answers
78 views

Find minimum node in Linked-List

I wrote a method that will return the minimum element in a linked-list that operates in O(1) time. I tested and everything works fine. However, I was wondering if there is anything that I can do to ...
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67 views

C stack for Linux and BSD

My stack uses char data and is not tested. I use it to save command in a unix pipeline for my own POSIX shell. Maybe you can find a bug or a possible improvement. ...
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1answer
53 views

Dynamic array stack and bag implementation

I've have methods for a stack and bag using a dynamic array in C. As far as I can tell everything is implemented correctly, but I'm wondering what I can do to improve this code. dynArray.h ...
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1answer
57 views

Stack implementation using a growing array

I'm working through Sedgewick's Algorithms book for fun and educational purposes. I am implementing a simple Stack<T>, using ...
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1answer
64 views

Balanced parenthesis in Ruby

I'm solving the "Balanced Parenthesis" problem in Ruby, and I came up with this solution. ...
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71 views

Stack and Queue implemented with a LinkedList

I am looking for feedback on my implementations of Queue, Stack, and LinkedList using Java ...
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155 views

Fuzzy Octo Guacamole interpreter

This is my code that interprets my own golfing and esoteric language, Fuzzy-Octo-Guacamole. It has 2 stacks to store information in, and various operations can be performed on each stack, or both at ...
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66 views

Comparing a string using a stack

Let L be the language defined as follows: The words are made up of strings of a’s followed by b’s. The number of a’s is always equal to the number of b’s. Examples of words that belong ...
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Fixed-length Stack in Java

I implemented a fixed-length stack in Java for use in my fractal generator program, an RPN calculator and my esolang interpreter. This is a generic stack, and goes over and above the call of duty in ...
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74 views

Java Stack Implementation with Generics

I've written an implementation of a Stack data structure using a linked list. Stack.java ...
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Checking for matching delimiters using multiple stacks or counters

I know my algorithm is very naive and slow for this problem. I would like to learn how to improve upon it? ...
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1answer
43 views

Custom concurrent stack implementation in Java

I don't want to use synchronized for sizeof method, any suggestion to implement the method thread safe? ...
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57 views
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51 views

Program looks for correct balance of ( [ and { in expression

I'm still new to programming. (First exposure was school about a year ago), and for some reason this problem really gave me a lot of problems trying to solve it. Can you help me understand what I ...
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1answer
116 views

Tail-recursive call vs looping for a Poker app

I'm developing a Poker app. It is almost done, and I'm looking for improvement. One of the things I wonder is whether I should change how I perform iterations. I currently iterate by using ...
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3answers
83 views

Sort stack in ascending order

I am using two more helper stacks to sort. Kindly suggest improvements in terms of space and time. ...
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1answer
42 views

Implement MyQueue using two stacks

I am taking a helper stack, which is used during dequeue. Kindly suggest improvement or some solution with less complexity. ...
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2answers
874 views

Stack having push, pop and return min in O(1)

I am using a class which is taking care of minimum value so far. Please let me know of any improvements or suggestions. ...
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1answer
102 views

Reverse Polish Notation Calculator in Java

I created a highly effective Reverse Polish Notation calculator using Java 8, but am uncertain if there are any better ways to handle the problem. Feedback on any evident taboos and bugs is greatly ...
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1answer
53 views
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Implementing Multi-File Programs in Vitsy

I'm the proud owner of the Vitsy programming language, which I've been working on for some time (except recently, because high school). It's only been used in PPCG so far, but I hope to expand it to ...
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108 views

Implementation of stack

Task: Create a class RPNStack which represents a stack of objects of type Node. Class RPNStack contains only one private field top of type Node. Objects of type Node represent data that ...
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1answer
43 views

Simple stack structure in C

I just started to learn C, and for practicing, I tried to implement a simple stack data structure, and I want to know if I'm making any mistakes, or how could I improve it: My stack.h: ...
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76 views

C Stack data structure

I have implemented a Stack data structure in C and I would like to know if there is something that could be improved. Stack using linked list: ...
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122 views

Sort a stack of numbers in ascending order only using push

I have a stack of numbers ranging from 1 to 1 million representing a pile of numbered DVDs. Given the stack in random order I am to sort the stack by only taking an element from the stack and push it ...
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106 views

Given a path to a directory, print the path to the biggest file in it

Here is my code. I simulated a stack rather than used some regular recursive algorithm because I needed to keep track of two variables: the path to the biggest file and its size. Besides I wrote a few ...
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1answer
76 views

Mutable stack in Racket

I'm learning Racket and have implemented a mutable stack, which is just a bunch of wrappers around an underlying struct containing a size and buffer list (so it's ...
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125 views

Infix to postfix implementation using a stack

I have implemented a "infix-to-postfix" function that takes as input a list representing the parsed expression, resulted from applying a certain regular expression to an expression, and I would like ...
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91 views

Sorting a Stack in ascending order

Here's my implementation of sorting a stack in ascending order. The problem statement is as follows : Write a program to sort a stack in ascending order (with biggest items on top). You may use ...
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122 views

Traversing a stack in my DFS algorithm for finding a path in a maze

I am trying to get this code running as fast as possible when traversing through my stack of my DFS currently the input files are like so: ...
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1answer
33 views

LinkedListy-Stack

I came across this interesting question while reading 'Cracking the coding Interview' and came up with a simple implementation. Any suggestions are welcomed. Imagine a (literal) stack of plates. ...
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95 views

C++ Stack implementation using std::list

I have the following 'interface' to the C++ std::list and I was wondering how I could make it go faster. In particular, it needs to be able to evaluate up to two ...
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143 views

SortedStack implementation in Java

This is a data structure that supports the push(), pop() and isEmpty() operations and ...
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3answers
354 views

Simple Stack Implementation in C

This is my implementation of the stack data type in C language. It is static meaning it does not grow in size. Any suggestions or feedback would be much appreciated. ...
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217 views

Stack implementation in Java

Here's my implementation of a Stack in Java, all feedback welcome. ...
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106 views

Memory leak in Java's stack implementation

Recently I was asked to implement a stack specifically for storing 'int' type data and find memory leaks. Isn't the garbage collector responsible for releasing all the memory? What are the possible ...
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376 views

Array-based stack data structure in Java

I've recently been writing simple data structures, even though they exist in the library it helps me understand them a lot better. ...
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70 views

Postfix evaluation using a stack in c

I have written a program to evaluate a postfix expression using a stack. I had my stack implementation using a linked list reviewed here, so I am only including the header file here. I have taken ...
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617 views

Array implementation of Java Stack

As an exercise, I wanted to make an array implementation of Stack, including most of the methods from the native Java Stack. ...
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435 views

Stack implementation with move semantics

I have implemented a basic stack just for fun. I've just started learning about move constructors and assignment and move semantics as a whole, so I would really appreciate some feedback as to whether ...
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256 views

Stack implemented using a single linked list

I am studying data structures and I have implemented a stack using a linked list. stack.h ...
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782 views

Simple FIFO and LIFO ferry simulator

I am trying to make a ferry simulator with one ferry that works like a stack and another like a queue. I have a working class for stacks and queues with pop/push; I am trying to figure out how to ...
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Stack using two queues

I have implemented the Stack using two Queues q1 and q2 respectively as shown below in the code. I would like to get you reviews on whether it's an efficient way of implementing it or now. For Pop ...
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576 views

Implementing two stacks using single array in java

Please review the code ...
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1answer
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ADT stack with a dynamic array (revision 1)

Here's the second draft of my ADT stack code which I posted here before after carrying out most of the improvements suggested there. I decided to expose a function called ...