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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InsertOnlyHashSet in C++
First C++ project: write a hash set for a specific scenario where I only need inserts and containment checks.
This is not AI slop, everything except for the avalanche function is hand written. Please ...
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Hashmap in C (with templates?)
I started implementing my own hashmap in C after taking inspiration from Git's hashmap API. As far as I know, the closest thing to templates in C are macros. I've seen that they are used in uthash or ...
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A simple C++ function converting the environment variables in main() to an unordered_map
I had this program:
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Desperately seeking a hashing function
A recent CR exchange led me to dust off and adapt some code I'd written a few years ago. Long, long ago, when core meant ferro-magnetic memory cells, I spent an hour formulating a "simple" ...
user272752
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Naive attempt at implementing a dictionary in C. Stack-based and O(n)
I am a C++ programmer trying to learn C.
Please critique my C code here. I am trying to make a small "hash table" that's \$O(n)\$ lookup. But, it is stack-based and so should be no slower ...
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Robin Hood Hash Table
The following code comes from an intrusive container library I am working on in C23. So far, it works correctly due to extensive testing and sample programs I have written with it. I have implemented ...
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Implementation of my multidict in Python
I need a code review for my implementation of my multidict in Python.
I'm not sure that my method below is implemented the best way:
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Separate Chaining Hash Table Implementation in C++
I've implemented a separate chaining hash table in C++ and would appreciate any feedback or suggestions for improvement.
Code:
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Optimized data structure mapping finite set of integers to values in C++
I'm looking for a mapping data structure, but knowing that the possible values of my keys are small numbers, I would like to trade memory for better performances (for both random access and value ...
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Check for key in dictionary without magic value comparison
I'm using pydantic in a project to check file formatting for an object, as well as pylint for linting. Whenever I read a file with an invalid format, I want to raise an exception with a descriptive ...
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Multiple key swap algorithm [closed]
I have a dictionary with key - data pairs. My data comes from excel sheets. When I create the dictionary my objects are placed in order by their keys ex. 1 -> data of sheet1, 2 -> data of sheet2 ...
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Optimizing Perfect Hash Table Implementation in C for Improved Performance
I wrote code that implements perfect hash table, according to its description in the book "Introduction to Algorithms by Thomas H Cormen", but the code does not pass time tests in contest. I ...
user282352
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A new Dictionary for VBA
The latest version of the Dictionary class presented in this question is available in the VBA-FastDictionary repository under the latest release.
Motivation
I ...
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Given two sparse vectors, compute their dot product
Problem Statement:
Given two sparse vectors, compute their dot product.
Implement class SparseVector:
SparseVector(nums) Initializes the object with the vector nums
dotProduct(vec) Compute the dot ...
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Program that brute forces to find the minimum dominating set
This program solves the minimum dominating set but it takes an insanely long time to run. In case you do not know, in graph theory, a dominating set for a graph G is a subset D of its vertices, such ...
