Toggle navigation
MeasureThat.net
Create a benchmark
Tools
Feedback
FAQ
Register
Log In
Array duplicate removal for duplicates exceeding `N`-number
(version: 0)
https://codereview.stackexchange.com/q/175067/120114
Comparing performance of:
original duplicate removal vs 2-pass approach vs filtering
Created:
8 years ago
by:
Guest
Jump to the latest result
Tests:
original duplicate removal
// Remove duplicates that occur 3 or more times in an array // keeping unique values and those with less than 3 function removeMany(arr) { const newArr = Array.from(arr).sort() let count = 0; let result = [] newArr.forEach((value, index, ar) => { count += 1; // refactored afterwards from (ar[index + 1] !== value) if (ar.lastIndexOf(value) <= index && count <= 2) { for (var i = 0; i < arr.length; i++) { if (arr[i] === value) { result.push(arr[i]) } } count = 0 } else if (ar[index + 1] !== value) { count = 0; } }); // +1 is there anyway to return a result that mimicks the original order of `numbers`? return result; // [1, 2, 2, 3, 4, 4] } const numbers = [1, 2, 3, 2, 4, 4, 5, 5, 5, 5]; console.log(removeMany(numbers));
2-pass approach
// Remove duplicates that occur 3 or more times in an array // keeping unique values and those with less than 3 function removeMany(arr) { let countMappings = arr.reduce(function(carry, item) { if (carry[item]!== undefined) { carry[item]++; } else { carry[item] = 1; } return carry; }, {}); return arr.reduce(function(final, item) { if (countMappings[item] <3) { final.push(item); } return final; }, []); } const numbers = [1, 2, 3, 2, 4, 4, 5, 5, 5, 5]; console.log(removeMany(numbers));
filtering
function removeMany(numbers, max) { const numberMap = numbers.reduce((map, num) => { map[num] = map[num] ? map[num] + 1 : 1; return map; }, []); return numbers.filter(num => numberMap[num] < max); } const numbers = [1, 2, 3, 2, 4, 4, 5, 5, 5, 5]; console.log(removeMany(numbers));
Rendered benchmark preparation results:
Suite status:
<idle, ready to run>
Run tests (3)
Previous results
Fork
Test case name
Result
original duplicate removal
2-pass approach
filtering
Fastest:
N/A
Slowest:
N/A
Latest run results:
No previous run results
This benchmark does not have any results yet. Be the first one
to run it!
Autogenerated LLM Summary
(model
llama3.2:3b
, generated one year ago):
Let's dive into the world of JavaScript microbenchmarks and explore what's being tested in this benchmark. **Benchmark Definition** The benchmark is designed to measure the performance of removing duplicates from an array, where duplicates exceed a certain threshold (N). The goal is to keep unique values and those with less than N occurrences. **Test Cases** There are three test cases: 1. **Original Duplicate Removal**: This test case uses a brute-force approach, sorting the array and then iterating through it to remove duplicates. 2. **2-Pass Approach**: This test case uses two passes: first, it counts the occurrences of each element using a Map data structure; then, it filters out elements with more than N occurrences. 3. **Filtering**: This test case uses the `filter()` method to directly filter out elements with more than N occurrences. **Options Compared** These three approaches are compared in terms of their performance and efficiency. * **Brute Force (Original Duplicate Removal)**: This approach has a time complexity of O(n log n) due to sorting, making it less efficient for large arrays. * **2-Pass Approach**: This approach has a time complexity of O(n), as it involves two passes through the array. It uses more memory than the filtering approach but is generally faster. * **Filtering (Original Duplicate Removal)**: This approach has a time complexity of O(n) and only requires a single pass through the array. **Pros and Cons** Here's a brief summary of each approach: * **Brute Force (Original Duplicate Removal)**: + Pros: easy to implement, no extra data structures required. + Cons: slow due to sorting, high memory usage. * **2-Pass Approach**: + Pros: faster than brute force, uses less memory than filtering. + Cons: requires two passes through the array, more complex implementation. * **Filtering (Original Duplicate Removal)**: + Pros: fast, efficient use of memory. + Cons: may not be as clear or intuitive as other approaches. **Other Considerations** When choosing an approach, consider the trade-offs between performance, readability, and maintainability. If you prioritize speed above all else, the filtering approach might be the best choice. However, if you need to implement this functionality in a production environment, the 2-pass approach or brute force approach might be more suitable due to their ease of understanding. **Libraries and Special Features** * The **Map** data structure is used in the 2-Pass Approach to count occurrences of each element. * There are no notable libraries or frameworks being utilized beyond the standard JavaScript features. * No special JavaScript features or syntax are being leveraged beyond standard array operations.
Related benchmarks:
Array duplicate removal for duplicates exceeding `N`-number
Array duplicate removal for duplicates exceeding `N`-number
Array duplicate removal for duplicates exceeding `N`-number
The Non Repeating Number
Comments
Confirm delete:
Do you really want to delete benchmark?