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.
392
questions
2
votes
1answer
79 views
Evaluating postfix expression on multidigit numbers
This is my solution for evaluating postfix expression using a stack. It does work on multidigit numbers, the problem I was struggling with last time. Now it works completely fine.
This is the stack ...
3
votes
4answers
128 views
Passing Programs To A Stack Machine Implemented In C++
I'm learning C++ by implementing a previous project I did in Python. This is a simple stack machine which evaluates mathematical expressions, e.g. pow(9, 12). The code to run this on the stack ...
3
votes
2answers
69 views
Stack API for generic values
I'm trying to create a stack library from scratch. It stores generic elements which are passed in void* pointers.
This is the defined structure:
...
3
votes
2answers
156 views
Check for max value in stack
Got this problem in a coding interview -
Get the max value of a stack in O(1).
The stack contains numbers only.
Please review my solution.
...
4
votes
2answers
1k views
Stack Implementation in JavaScript
I am learning data structures and below is my implementation of a stack in JavaScript. I didn't want to use built in functions for an array because in JavaScript that would be too easy, so I made my ...
2
votes
3answers
55 views
C++ evaluating an arithmetic expression in RPN format using ADT stack
Write a program that uses an ADT Stack to evaluate arithmetic expressions in RPN format. The contents of the stack should be displayed on the screen during evaluation. The allowed arithmetic operators ...
6
votes
1answer
205 views
Calculator in C - Parsing arithmetic expression using the shunting-yard algorithm
This is a simple arithmetic calculator, which parses mathematical expressions specified in infix notation using the shunting-yard algorithm. This is one of my personal projects and I would love to ...
0
votes
0answers
78 views
UVA 101 - "The Blocks Problem"
I have been solving the problem from UVA 101. In this problem, there will be at most 24 position in a row at beginning, and this array is zero-indexed, and for each ...
1
vote
1answer
56 views
Stack of integers in C
I'm learning C, and currently I follows C99 standard. Here is my implementation of integer-stack, which is just a stack you can do: push, pop, and print the content ...
3
votes
1answer
66 views
Python Console App | Is there a better way to go back a page?
I have a system for going back to a previously-visited page in a Python console application; it works well enough, but I feel that there could be a prettier way of doing it. Does anyone have any ...
1
vote
0answers
169 views
Add missing left parentheses in Java [closed]
I wanted to write a program that takes from standard input an expression without left parentheses and prints the equivalent infix expression with the parentheses inserted. For example, given the input
...
3
votes
2answers
82 views
A toy example of the concurrent stack via atomic variables and CAS pattern
I've written a toy example of the concurrent stack which has only three functions push(), peek(), and ...
0
votes
1answer
64 views
Generic stack implementation in C
I haven't separated the stack code into its own header and source yet, this is just a proof of concept for now. Haven't chosen better function names yet because I ultimately want to integrate this ...
1
vote
0answers
78 views
Monotonic stack - complexity analysis
I tried following the official solution of LC975 (https://leetcode.com/problems/odd-even-jump/), using a monotonic stack - i.e., I reimplemented their solution (Approach 1) from python in C++.
TLDR ...
2
votes
1answer
85 views
C++ implementation of a Stack with dynamic C-style array
I implemented a Stack in C++ using a dynamic C-style array. I tried sticking to the most important functions a Stack has to have to be usable. This is meant to only be for integers. I appreciate any ...
6
votes
2answers
99 views
Error Code Stack Trace and Propagation Library in C
I've been programming in Go and I enjoy how easy it is to create descriptive errors and propagate them up the call stack. I wanted that sort of ease and consistency in C so I created a small error ...
4
votes
1answer
76 views
Assemble network packet on stack for iovec
The recurring problem to assemble a network packet out of payload, sequence number, header, and other misc. information is mostly solved either on the heap (e.g. appending to a ...
2
votes
2answers
1k views
Dynamic Array Based Stack in C
I wrote a dynamic stack in C that uses an array as a structure. I tried to maintain O(1) for push and pop and believe I have done so. I want to know what can be written in a cleaner way and if there ...
3
votes
2answers
433 views
Convert infix regular expression notation to postfix
This is a small part of a larger program for implementing a limited syntax regular expression constructor using Ken Thompson's construction algorithm. Converting to postfix before the regular ...
7
votes
1answer
4k views
Optimizing Efficiency in a Stack
I'm solving a problem on HackerRank where I'm required to implement a simple stack.
It's passing all the tests except for the last 4 where it fails due to surpassing the time constraint of 10s. ...
2
votes
1answer
341 views
Kotlin Stack using an ArrayList to compare and remove elements
Is this a performant strategy to implement a stack in Kotlin to compare and delete values?
Expect
Create a stack in order to compare an array of asteroids (ASTs) and handle collisions (deletions), ...
10
votes
2answers
587 views
An attempt at a toy Vm
I usually use c++ so it may not be best practice for c.
This is a stack based toy vm and as a result it is very primitive, and it has no bitwise
instructions
64k might be a bit overkill for a toy vm.
...
1
vote
1answer
86 views
Stack Implementation Using Linked Lists
I have tried Implementing Stacks Using Linked Lists, and would like some tips and tricks regarding optimizations or ways to simplify/compact processes.
It has 3 functions, Push, Pop, and Peek (For ...
1
vote
0answers
21 views
regex on a log file utilizing stacks and queue's in Java
This would be for a MUD client, which has elements of a sort of telnet bot.
Here, there's ...
-3
votes
1answer
47 views
What's wrong with this stack implementation? [closed]
My CS teacher sent me the following code for implementing the stack. I've been programming for a few years in higher-level languages, but have rather weak experience with C++. I mean, this code just ...
9
votes
4answers
3k views
Simple Stack implementation in C++
I've recently started teaching myself basic C++ and decided to implement a simple stack with pointers.
...
1
vote
1answer
393 views
Concurrent Queue with enqueue and dequeue using Stack as underlying data structure
This is a mix of data structure and multi threading concept based question. (This is only for understanding and learning purpose) The language for the solution : Java
A Queue with FIFO behavior needs ...
2
votes
2answers
67 views
Queue By Using Stack
I have implemented a queue by using a stack data structure. How could I improve it?
...
7
votes
3answers
233 views
Dynamic stack implementation in C
I've been studying C for a while, as a programmer coming from a C++ background, I'm used to the standard library, STL, etc., and I quickly realized that I need some kind of a containers library/data ...
1
vote
4answers
927 views
Exercise: Design a Stack
Exercise: Design a Stack
A Stack is a data structure for storing a list of elements in a LIFO
(last in, first out) fashion. Design a class called Stack with three
methods.
...
3
votes
2answers
1k views
3
votes
3answers
534 views
Stack implementation using linked-list
typedef struct Stack {
char v;
int x;
int y;
struct Stack* next;
} Stack;
Above is my stack struct.
...
4
votes
1answer
65 views
C pointer based growable stack rev2
Following on from my previous question: C pointer based growable stack
I have made some improvements (hopefully!) based on the very helpful comments and suggestions.
I have checked that the stack can ...
7
votes
3answers
1k views
C pointer based growable stack
This is my first attempt at writing a C program, it a generic stack that can grow accordingly. It appears to work correctly, however I am worried that is just a fluke and I could be doing something ...
4
votes
1answer
378 views
Codility Fish (queue) programming challenge
Today I have attempted a Codility exercise "Fish" (https://app.codility.com/programmers/lessons/7-stacks_and_queues/fish/), and I have to say I found it to be:
1) Not necessarily "easy" as implied by ...
2
votes
2answers
98 views
Designing a stack such that getMin() is both constant time and constant space
I'm attempting the SpecialStack problem on GeeksforGeeks.
Design a data-structure SpecialStack (using the STL of stack) that
supports all the stack operations like push(), pop(), isEmpty(),
...
1
vote
1answer
130 views
Syntax Checker C++ Data Structure - Stack
Syntax Checker is a very common question of c++ programming using the data structure stack. However, this is the advanced level base on this question I found in a reference book. Here is the question:
...
17
votes
7answers
3k views
Stack data structure in Python 3
I have implemented a stack in Python 3, and it works well. If anything needs to be improved, I would appreciate the criticism.
...
6
votes
1answer
2k views
Doubly Linked List using Stack in c++
Just started learning/relearning data structures for the semester exams. Most of the examples found online are too cluttered or bloated.
For myself, I implemented it from theory I learned.
It works....
1
vote
1answer
2k views
Codility's stonewall 100% solution - different paths such as if,else if,etc, do the same thing
Here is the task description for the codility's stonewall problem. I would like to get a feedback on my code, and I specify at the bottom what the title states. (I had to make the figure by hand, ...
3
votes
1answer
184 views
Codility voracious fish are moving along a river, solution in C#
This is the task's description. My code gets 100% task score. Is it good code yet? (I think I'm getting a lot better, since I started solving this codility's exercises and posting here, but I always ...
1
vote
0answers
248 views
LeetCode: Daily Temperatures C#
https://leetcode.com/problems/daily-temperatures/
Given a list of daily temperatures T, return a list such that, for
each day in the input, tells you how many days you would have to wait
until ...
2
votes
2answers
938 views
Creating a stack class in C++
Create a class called Stack for storing integers. The data members are
an integer array for storing the integers and an integer for storing
the top of stack (<...
5
votes
1answer
72 views
An alternative algorithm for sorting a stack using only one additional stack
From "Cracking the Coding Interview":
Write a program to sort a stack in ascending order (with biggest items on top). You may use at most one additional stack to hold items, but you may not copy ...
6
votes
5answers
137 views
Safe stack abstraction
Here is the stack abstraction that I've written. I've designed it to be safe and without undefined behavior.
I use ugly_cast to discourage casting and to make ...
13
votes
5answers
3k views
Stack class in Java 8
I have a exercise where I have to write a Stack class with the push and pop methods. The code compiles and works as it should. Are there better practices to use in my code? Is there something I should ...
4
votes
2answers
90 views
Basic Stack in C++ Using Array
I wrote a stack class in C++ using arrays of fixed width. Could anyone review my code ? I didn't comment on any of the functions, because I thought class itself is self explanatory. Is it a wrong ...
5
votes
2answers
728 views
Bracket balance checker in Python
Implement a feature for a text editor to find errors in the usage of brackets in the code.
Input: sorted(list(zip(a, b))
Output: False
Input: ([{}, {}])
Output: True
Here's my implementation in ...
5
votes
3answers
102 views
Unix tail command using stack
I'm working on a version of the Unix tail command that works by iterating over a file, pushing line by line into a stack. Finally, the number of desired lines will be popped and printed to the screen. ...
11
votes
3answers
4k views
HackerRank Implement Queue using two stacks Solution
Challenge
Problem Statement - Implement a Queue using two Stacks
I implemented dequeue() in \$O(1)\$ at the cost of enqueue() ...
