A data structure is a way of organizing data in a fashion that allows particular properties of that data to be queried and/or updated efficiently.
2
votes
0answers
31 views
My own version of a search binary tree
I wrote my own version of a search binary tree in Java. Could someone kindly review it?
...
3
votes
1answer
36 views
d-ary heap in C
Now I have this d-ary heap data structure. Note that for d = 2 this is a binary heap. The client programmer specifies the value ...
4
votes
1answer
40 views
Unordered (hash) map for C
I am still working on basic data structures for C. Now I came up with a hash map:
unordered_map.h:
...
6
votes
0answers
24 views
Creating a pseudo Pivot Table / Database using a 4-D array
Why am I not just using a Pivot Table / Database?
a) I've never ever used either before. And I don't have time to learn how before this project needs to actually be finished.
b) The final output ...
1
vote
0answers
11 views
Segment tree with lazy propagation
This is the implementation of segment tree with lazy propagation. Could you please review this code so that I can improve my ...
3
votes
1answer
44 views
Ordered map for C using AVL tree
I was in the mood for some data structures and I decided to code up an ordered map using AVL tree. I will post only map.h and ...
-2
votes
0answers
29 views
Inseting a node in binary search tree [closed]
When I'm inserting a node on the below binary tree,it is giving incorrect answer,although logic seems fine to me.
...
2
votes
1answer
27 views
Menu driven program to represent polynomials as a data structure using arrays
Write a menu-driven program to represent Polynomials as a data
structure using arrays and write functions to add, subtract and
multiply two polynomials; multiply a polynomial with a constant, ...
6
votes
1answer
23 views
Implementing a van Emde Boas tree in Rust
I wanted to implement a van Emde Boas Tree in Rust, to start learning the language. Much of my implementation is derived from the pseudo-code on wikipedia, with the exception that empty subtrees are ...
4
votes
2answers
53 views
InfixDictionary: Data structure for Infix string lookup
I needed a data structure to quickly find all previously inserted values, that have the given string as key or substring (full text search).
At first, I tried out some tree structures (infix ...
2
votes
1answer
39 views
Get K most frequent tokens from a token stream
This is an interview problem:
Given a token stream, find the K most frequent tokens in real time (the order of these k tokens does not matter).
My approach:
Use a hash table (...
5
votes
4answers
297 views
A data structure with push(int x), pop(), min() and max() in O(1)
I have written this Java code for a data structure which includes 3 stacks to supports four operations in \$O(1)\$: push(int x), ...
4
votes
2answers
76 views
Two sum algorithm variant
I need to compute the number of target values \$t\$ in the range: \$-10000 \le t \le 10000\$ (inclusive) such that there are distinct numbers \$x, y\$ in the input file that satisfy \$t= x+y\$. I have ...
4
votes
1answer
106 views
2D Fenwick-tree with combinatorics and modular arithmetic
This is a contest problem;
Description:
In the winter, children started to build snowmen. The snowmen were becoming adorable, except for a detail: none of them had a nose. The king, touched, ...
2
votes
2answers
23 views
Counting Bloom filter library in Java
This snippet is a counting Bloom filter supporting removal of elements as well. Instead of a bit vector it maintains a vector of "bucket counters". Also, the API supports well taking your customised ...
3
votes
1answer
81 views
Calculating the sum of array elements to the left and right
I am using C++ to code the following logic:
An Array is given we have to traverse the array such that sum of array elements to its left must be equal to sum of elements to its right.
BTW this is ...
3
votes
2answers
36 views
Skip-List that uses a Singly-Linked-List implementation
I've implemented this skip-list yesterday, and I'd like suggestions on how to improve this code, and my coding practices.
...
5
votes
2answers
119 views
Merge k Sorted Arrays
Please review my answer for this interview question:
Merge k sorted arrays, using min heap.
...
11
votes
1answer
132 views
I made an implementation of std::deque, in my own way…?
In fact, entire deque header, though.
According to Wikipedia, common implementations of std::deque include:
Storing deque contents in a circular buffer, and only resizing when the buffer ...
4
votes
0answers
52 views
Swap items of a linked list in pairs - revision 5
Here is the source of the question.
Given a singly linked list, swap the list items in pairs (reconnect
the pointers, not simply swap the values). For example:
Before: A->B->C->D
...
8
votes
3answers
100 views
Check if all leaves are at same level in a binary tree
I have written this code for checking whether all leaves are in the same level or not, in a binary tree. Any suggestion or improvement is appreciate.
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-2
votes
5answers
90 views
What is the better way to write such code in PHP?
Is there a better way to write the below code?
...
5
votes
1answer
160 views
Algorithm that tells the user what current “status” they fall under based on their current time in comparison to an array of meeting data times
This is an algorithm that takes in an ArrayList of objects that store information on meeting/event schedules. This algorithm's purpose is to check and see what the ...
2
votes
1answer
36 views
Create a text index of files
This program creates a text index of 3 different files in Python. While this works correctly, I am still a beginner in Python. I used a list of class objects. Can this code be further optimised?
...
2
votes
1answer
72 views
HackerRank Regex Challenge: Detect HTML Tags
Problem Statement
In this problem you will use regular expressions to help you detect
the various Tags used in an HTML document.
Here are a few examples of tags:
The "p" tag for ...
3
votes
1answer
26 views
Container supporting PeekMax, PeekMin, Sum, and PeekNextToMax v2.0
This is another part of the update to this question. The interfaces are in this question.
To summarize, the class is a generic container similar to MaxHeap, but only needs to support the following ...
1
vote
1answer
36 views
Interfaces & Factory for generic container supporting PeekMax, PeekMin, Sum, and PeekNextToMax
This is a partial update of this question.
An implementation of these interfaces is in this question.
To summarize, the class is a generic container similar to MaxHeap, but only needs to support the ...
4
votes
1answer
67 views
Matching strings
Basically I solved this question on one of the competitive websites:
Given the total n number of String on first input, n input follows:
We have to find such pairs of string (i,j) such that ...
0
votes
1answer
62 views
Remove Duplicates from Sorted List — LeetCode Solution in C
Given a sorted linked list, delete all nodes that have duplicate numbers, leaving only distinct numbers from the original list.
For example,
Given 1->2->3->3->4->4->5, return 1->2->5.
Given ...
12
votes
1answer
87 views
Compile-time data structure generator
In response to another recent question I mentioned that one mechanism to avoid runtime overhead for creating a data structure was to create it at compile time and use it directly. Since there was ...
3
votes
1answer
53 views
Priority stack in Java
I have this (simple) data structure that maintains multiple LIFO stacks. Each such stack is assigned a priority. The less is the value of a priority key, the higher the priority. Pushing operation ...
9
votes
2answers
92 views
Simple inventory system - Part 2
I've refactored my previous inventory system, and added a few features like removing items from the Inventory class, easily obtaining the current selected item ...
2
votes
3answers
47 views
Transforming data from an array of objects to a nested array of objects
I have an array of objects where each object has a datetime key/value pair:
...
6
votes
1answer
362 views
Very simple inventory system
To learn F#, I've implemented this very simple inventory system. While I'm proud that that it's my first program, and that it works, there are still a few areas that I'd like tips on, namely these:
...
2
votes
1answer
32 views
Chained hash table implementation to store student's information
This is my implementation of a Hash Table to store information about a student. Everything seems to work as expected, but I'd like some feedback on the following:
Is my style good? Is it easy to ...
3
votes
1answer
88 views
Detecting cycles
This is a challenge question from codeeval.com:
Given a
sequence, write a program to detect cycles within it. Input sample:
Your program should accept as its first argument a path to a ...
6
votes
1answer
109 views
Trie data structure in Java
I have implemented a trie data structure in my way, though it is very similar to what major implementations I found but would like to get it reviewed by experts.
I don't see the need to store ...
2
votes
0answers
31 views
Inheritance across data in JavaScript
I'm creating a JavaScript app for a esoteric language, Marbelous. One of the features of this language are the devices. Each cell has a device, and each device has certain properties.
In order to ...
-6
votes
1answer
75 views
6
votes
1answer
65 views
Finding most frequent words from Google N-Gram dataset
I have written a program to process Google 1-Gram dataset in order
to obtain the list of most frequent words. This is my second more or less
working program in Haskell, so I really want to know if it ...
0
votes
1answer
46 views
Implementing find middle element of singly linked list without using 2 pointers
There is a solution floating around about using 2 pointers. But I decide to keep the implementation much simpler by using basic constructs that works use to build basic methods of a singly list list ...
8
votes
5answers
653 views
Find longest lines from a file
This is a challenge question from codeeval.com:
Write a program which reads a file and prints to stdout the specified
number of the longest lines that are sorted based on their length in
...
7
votes
1answer
48 views
Querying houses similar to a given house
I was given this task as an interview coding challenge and was wondering If the code is well structured and follows python guidelines. I chose to sort the houses based on a similarity metric and then ...
3
votes
5answers
234 views
Making ArrayList.containsAll run faster
Whenever using ArrayList, the method containsAll(collection) runs in time \$\mathcal{O}(mn)\$, where \$n\$ is the size of ...
6
votes
1answer
284 views
Caterpillar uneaten leaves
K caterpillars are eating their way through N leaves, each caterpillar
falls from leaf to leaf in a unique sequence, all caterpillars start
at a twig at position 0 and falls onto the leaves ...
11
votes
3answers
1k views
Fastest and minimal random access data structure in Java
I have written up a data structure in Java that supports the following features:
get(i)
set(i, e)
...
1
vote
1answer
37 views
Interface for fixed-size container supporting max, min, sum
I had posted this previously as part of Generic container similar supporting PeekMax, PeekMin, Sum, and PeekNextToMax but I think it was to big a morsel for people to chew on. So I'm splitting it up.
...
3
votes
3answers
78 views
Dynamic resizeable array
How can I improve this code for a dynamic and re-sizable array data structure?
Array.h
...
6
votes
1answer
68 views
List querying capabilities in Python 3.x
Either out of boredom, or my odd fascination with LINQ and SQL, this, thing, was created. Essentially, it provides list querying capabilities. At the moment, you can only query lists based on ...
3
votes
2answers
57 views
Linked list insertion
I have written the code below for inserting an element at the position specified by the user.
I have seen the code in multiple books, and they have always used two pointers in the function that ...
