Questions tagged [hash-map]
A data structure that uses a hash function to map identifying values, known as keys, to their associated values
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IndexedArray Class: Uses a Dictionary Keys to Index a 2 Dimensional Array of Values
This class encapsulates a 2D Array and a Scripting Dictionary. Values are add or returned from to the Array using a Key and a ColumnIndex, e.g. ...
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Agent-based Immutable Map
I am in the process of removing the last few pieces of mutable state from an F#-based distributed system. Some of the remaining mutable state is a ...
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Bidirectional bijective hash map in C
I have this bidirectional hash map in C for dealing with bijective maps. Each key mapping consists of a primary key and a secondary key, and I can ask the data structure to give me a secondary key ...
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Chapter 8 Challenge: Add employee names to a department
The boring but exciting challenge:
Using a HashMap and HashSet, create a text interface to allow a user to add employee names ...
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Recursive conversion from ExpandoObject to Dictionary<string, object> #2
Because my original question was lacking many details, I have been advised to ask a new question.
I will repeat the important parts of the original question and add examples etc to hopefully make it ...
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Decode HTML Entities in VBA using regex and dictionary
I receive HTML-encoded text that includes named and numbered entities, and I need the decoded HTML.
There were just too many bad solutions for this online.
I use regex pattern ...
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HashMap exercise, Rust book Ch.8
I'm learning Rust by learning the Rust programming language book. I'm now implementing the solution for the third challenge.
Using a hash map and vectors, create a text interface to allow a user to ...
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Elegant way to alter datasets with explicit filters
I would like to write a small helper to filter datasets. Each dataset is a dictionary and some filters I want to apply are common to all the datasets.
That my needs, I wrote this following pattern:
<...
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General Purpose C Dictionary
I'm trying to create a general purpose C dictionary (as an opaque data type) capable of dynamically allocating basic types (ints, floats, strings and longs) as well as accepting void pointers to ...
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Linear probing 16 hashmap elements in parallel using SIMD instrinsics
For my hashmap implementation, I'm caching hashes for each map element in an array of length NBUCKETS, where each element corresponds to an element in the hashmap. ...
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C# code for minimizing the sum of an array by dividing it's elements (repetition allowed) by 2 for k times
The assumption is that k is quite large as compared to no. of elements in the array and division by 2 returns ceiling of the result.
Request for your review and suggestions for further improvements ...
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Alternative for VLOOKUP/Index-Match in VBA
I am sharing this function I wrote with the community to provide an alternative to slow VLOOKUP and/or Index-...
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A map class based on an AVL tree
Here's an implementation of a class which is similar to std::map, but it's not a complete/identical implementation.
I know C pretty well, but am a beginner with C++...
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Compute damages and savings for motor insurance claims
I am working on some claims data, where I have features such as
The descriptions of the columns are: (A) the year of claim, (B) who's the insuring company (C) whether the vehicle is driven, (D) ...
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3Sum - leetcode
Question:
Given an integer array nums, return all the triplets [nums[i], nums[j], nums[k]] such that i != j, i != k, and j != k, and nums[i] + nums[j] + nums[k] == 0.
Notice that the solution set ...
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Modeling data from Excel sheets to parse to Excel sheet
Background:
I have close to 50 excel files - I cannot change the data source - and I steadily get more.
My task is to make sense of all that data and, lo an behold, save that as another excel file (I ...
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Hashtable Visualizer in TypeScript
Implementation is based on the MVC design pattern, with callbacks to allow model and view to communicate with controller.
Concerns:
It's not ideal to have async code inside the model, i.e the model ...
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Converts Pandas and Numpy into Dictionary and Converts back to original format for data split
I'm trying to refactor some code so that it does not have so much repetition to it. What I'm trying to do is create an input for a multiple channel/input neural network. The features that are being ...
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Linkedlist & hashmap _duplicates removal
I have implemented a LinkedList removal fo duplicates class by using HashMap.
Looking forward to your reviews.
Thanks.
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Pythonic way to cast a dictionary into a pd.DataFrame with two columns?
I have a dictionary where for each key, a single value is stored. Say
import pandas as pd
dd = {'Alice': 40,
'Bob': 50,
'Charlie': 35}
Now, I want to ...
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Solution to 3Sum problem on Leetcode using HashTable
The problem of 3sum is described as:
Given an array nums of n integers, are there elements a, b, c in nums such that a + b + c = 0? Find all unique triplets in the array which gives the sum of zero....
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Coding Challenge Solution - Find Number of Elements in a range in \$O(1)\$ with preprocessing
Overview
This is my solution to the following Coding Challenge - Find Num of Elements in a Range in \$O(1)\$ with Preprocessing -
Given an array and max element in the array, find the number of ...
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Convert flat object hierarchy to json
I do work for a project currently, where the data is send to the server as application/x-www-form-urlencoded (which is bad, and it should be JSON, but unfortunately I am not able to change this one).
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Ruby Hash to XML
I've just made this "serialization" module in Ruby that takes a hash and outputs a XML string.
...
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A fast integer key map in Java via a van Emde Boas tree
Introduction
The following data structure is a dictionary mapping primitive int values to any value type. Basically, under the hood it is a hash table, where a ...
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Spellchecker program is having issues due to vowel checking method
This program takes in a list of 275k or so words from '/usr/share/dict/words' and loads them into HashSet. It then takes in a list of 1000 words (taken from the dictionary and are scrambled (vowel ...
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Ordered-by-insertion map
The main problem that I tried to tackle here was trying not to have the erase method to be \$O(n)\$. I kept two data structures: a linked-list of pairs and a map of a key and a pair containing a value ...
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List of lists from file
I'm writing a sub-routine in AppleScript to get text from a file and insert that text in a list of lists forming a dictionary.
Text File:
a:b
c:d
e:f
Expected ...
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HashMap with binary search tree for chaining
My friend was asked to implement a hashtable with a binary search tree. I tried practicing it myself, and it turned out to be very verbose. I need suggestions to clean this up!
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Map operation to update data | Hazelcast IMap returns clone object
I have a nested hazelcast distributed map:
Map<CountryId, Map<CityCode, Map<data_key,data_value>>>
where "data_key" is "population", "...
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Universal nested get/set for trees in Python
Based on this source, I've made the following universal get / set function, to make it possible to work on OrderedDict trees for example.
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Hash Table Implemented by Javascript
I recently tried to implement a simple hash table using Javascript. Could anyone help me review my implementation?
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Implementing a HashTable in Objective-C
I am trying to implement a hash table in Objective-C. I did some testing and the implementation seems to work. I am using an NSMutableArray to store linked lists ...
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Java Concurrent Multimap
I've implemented a concurrent multimap that support concurrent put and remove but I'm unsure of its correctness. I would appreciate your feedback.
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What’s the correct usage of volatile keyword in this Concurrent dictionary implementation?
Can I get some guidance around the usage of volatile keyword and design of the existing concurrent dictionary implementation, please.
Here are a few design ...
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Directed weighted graph in C
I am working on a project that requires a directed weighted graph data structure. It looks like this:
graph.h
...
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Counting Cram game positions in C
This code counts the number of possible positions in the game of Cram on a mxn board.
EDIT 1: In the original question I mistakenly mentioned that this number is ...
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A simple Java integer hash set - follow-up
(See the previous version.)
(See the next version.)
After incorporating changes in the previous post, I came up with this implementation. However, I left hashing as it is.
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Global Dictionary Class
For a Django-Server I use several custom Error-Codes, error-titles and descriptions, possibly other fields might follow.
I'm using right now a basic global dictionary.
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What is the best implementation of a ignore case dictionary In C#
Imagine we have a custom dictionary class which is derived from Dictionary<string, object>. Dictionary is case-insensitive about keys and elements arrange is ...
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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 ...
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Simplifying decision tree when working with map which has two keys and value as a slice
Can this logic not be simplified more, the code works, but it has become too much of a spaghetti. The requirements are that there should always be one connection if possible in ...
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HashSet without collision
I have written a custom HashSet and though it isn't completed yet (this code does not consider test cases with collisions), I would like to know if there is anything I can improve in areas of clean ...
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Custom HashMap implementation in Java with Linear Probing
I have taken a stab at implementing a HashMap in Java. To deal with collisions I implemented sort of a LinkedList using a dataNode. I am not very confident of my implementation hence looking for some ...
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Building maps for Dgraph integration tests in Java 8
I want to refactor this in Java to reduce my code duplication.
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Rust book ch 13 Closures + HashMap exercise
So the exercise is as follows:
Try modifying Cacher to hold a hash map rather than a single value.
The keys of the hash map will be the arg values that are passed in,
and the values of the ...
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Filling values for nested dictionaries
I have a text file where any name followed with sequence word is considered a dictionary. The task is to go through the keys and values of a particular dictionary, which is already identified, and see ...
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java - A* search algorithm
I'm having trouble with my homework implementing A* search algorithm in java, I'm given the graph, origin and destination, I had to follow some specific tasks in the homework so the code might be a ...
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