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Questions tagged [stack]

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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5
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1answer
2k views

Stack implementation in Python 3

I'm learning Python by implementing commonly used data structures. My primary language is Java, thus would like to know if I'm being Pythonic enough. Any means to better up will be appreciated. ...
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1answer
239 views

Implementation of a generic Stack in C++ [closed]

I've implemented a generic Stack in C++. I would like a code review in regards to my code, especially on whether or not my implementation satisfy the following 4 ...
1
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1answer
81 views

Stack implementation with exceptions [closed]

I would like to know if this is a great stack implementation. I created my own exception. Was that a bad idea or unnecessary? Should I have just thrown a IndexOutOfBounds exception instead of my own. ...
4
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2answers
109 views

Proper Stack Implementation

I want to know if this stack is implemented properly. Previously I was told a Linked List contains an inner class that represents a node and the outta class that represents the structure. Does that ...
2
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1answer
704 views

Stack implementation with shared_ptr C++11

stack.hpp ...
9
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2answers
2k views

Managing a programmatically accessible stack trace

VBA has a call stack... but there's no programmatic way to tap into it, which means in order to get a stack trace for a runtime error, one has to manage it manually. Here's some example code that ...
4
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2answers
115 views

Designing stack and queue from scratch in C

As a beginner and curious guy I'm interested in implementing data structures and algorithms from scratch. Here's my implementation of Stack and Queue, the most fundamental data structures. Are ...
4
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2answers
662 views

Stack implementation in ES6

Finally happy to see that now we can have iterators and generators. I also need to try to have private properties too so that we have well encapsulated data structures and I see that there are Proxies ...
4
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1answer
315 views

Implement a queue using two stacks

I tried to implement a queue using two stacks. I saw there are questions about this topic, but in my example, I used build-in stack from java. My question is, can someone give me some advice to make ...
5
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2answers
4k views

Poisonous Plants

I have solved the following problem. My code works but Hackerrank says that I can do faster: There are plants in a garden. Each of these plants has been added with some amount of pesticide. ...
2
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2answers
302 views

Finding the Least Common Ancestor of a Binary Tree

Input a binary tree (the root node) and 2 other nodes that need to be assessed for finding the least common ancestor (LCA) Code: a. Finding the nodes first with either ...
3
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2answers
246 views

Queue using Stack

I implemented this solution for the problem. Please provide feedback and review if this can be improved in any way. ...
3
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1answer
134 views

Stack from Linked List

I have written a program that takes a linked list and then converts it to a stack. I would like a code review for my program. Thanks in advance. Stack.java ...
2
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0answers
206 views

Improving time efficiency of finding maximum area rectangles in a histogram

Here's my solution but I am looking for ways to improve the time complexity of solution. Also this question is categorized as being solved by stack so I would like to know how to approach it using ...
0
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1answer
304 views

Stack that does Push, Pop and Median in O(1)

Here are two implementation of a stack that does Push, Pop and Median in O(1). Invite comments on complexity and betterment. Option - 1 ...
2
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4answers
934 views

Reverse Polish Notation Evaluation in Java

I would like to hear feedback about my code both in term of improving efficiency if possible or using other data structures. Also go ahead and let me know about code styles/patterns. ...
3
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1answer
94 views

Queue implementation using two stacks

Here's my code and I want to know if there's a better method for doing so. While the question has stated two stacks I wonder if we could do only with one as well? ...
2
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1answer
420 views

Building a Stack with C structs

After reading the book from which this example is from I started using APIs like this ...
4
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3answers
5k views

C++ Dynamic array based stack

I have implemented a dynamic array based stack. Can someone point out any pitfalls or things that can be done better? MyStack.h ...
4
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1answer
1k views

Sort stack using two stacks

My program is supposed to sort a stack such that the smallest item are on the top. I can use a temporary stack, but you may not copy the elements into any other data structure. The program works ...
1
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0answers
72 views

Mergesorting a stack in Java - a new algorithm

(See the previous iteration.) Now I have implemented a stack merge sort that does not have to reverse every substack after sorting it, and it allocates the two auxiliary stacks only once prior to the ...
1
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1answer
135 views

Mergesorting a stack in Java

(See the next iteration.) 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....
4
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1answer
2k 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 ...
2
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0answers
64 views

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 ...
6
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2answers
850 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. ...
2
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2answers
88 views

A stack optimized for filter queries, written in the C++ preprocessor

Given a stack with N elements and a query Q, we need to find all elements of stack for which ...
6
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2answers
3k 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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1answer
106 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. ...
3
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1answer
1k 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 ...
5
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1answer
266 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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2answers
3k views

Balanced parenthesis in Ruby

I'm solving the "Balanced Parenthesis" problem in Ruby, and I came up with this solution. ...
2
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2answers
655 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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3answers
297 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 ...
3
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2answers
3k 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 to ...
2
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2answers
2k views

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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1answer
245 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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2answers
132 views

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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2answers
1k 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? ...
2
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2answers
2k views

Flatten iterator for nested list in python3

flatten.py ...
2
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2answers
67 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 ...
3
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1answer
147 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 tail-...
2
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2answers
107 views

Templated Stack of 5

This is my first time using C++ Templates to make a data structure. I have written a program to implement a stack of up to 5 items. ...
3
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3answers
2k views

Sort stack in ascending order

I am using two more helper stacks to sort. Kindly suggest improvements in terms of space and time. ...
1
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1answer
52 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. ...
11
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2answers
1k 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. ...
5
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1answer
19k 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 ...
4
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1answer
607 views

Check correctness of brackets in file with stack + error detection

Task: My implementation: ...
8
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1answer
77 views

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 ...
6
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2answers
2k 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 are ...
3
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1answer
137 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: ...