43 lines
1.8 KiB
C++
43 lines
1.8 KiB
C++
|
/*#############################################################################
|
||
|
|
## Author: Shaun Reed ##
|
||
|
|
## Legal: All Content (c) 2021 Shaun Reed, all rights reserved ##
|
||
|
|
## About: An example implementation of bucket sort using a custom library ##
|
||
|
|
## ##
|
||
|
|
## Contact: shaunrd0@gmail.com | URL: www.shaunreed.com | GitHub: shaunrd0 ##
|
||
|
|
###############################################################################
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include "lib-bucket.hpp"
|
||
|
|
|
||
|
|
#include <algorithm>
|
||
|
|
#include <list>
|
||
|
|
#include <vector>
|
||
|
|
|
||
|
|
|
||
|
|
void BucketSort(std::vector<float> &array)
|
||
|
|
{
|
||
|
|
// For this example, we need an array of linked lists
|
||
|
|
// + Each value of this array will be referred to as a bucket
|
||
|
|
// + Each list stores the values that fall within the range of that bucket
|
||
|
|
std::vector<std::list<float>> bucketArray(BUCKET_ARRAY_LENGTH);
|
||
|
|
|
||
|
|
// Truncation to zero will always floor the result of division
|
||
|
|
// + If the bucket contains negative values, convert them to their absolutes
|
||
|
|
// + Run BucketSort on the abs values, then convert them back to negative
|
||
|
|
// ++ For a mixed-bag of negative and positive, track which values you absolute
|
||
|
|
// ++ Then only negate those values after BucketSort
|
||
|
|
for (const auto & value : array) {
|
||
|
|
bucketArray[value / static_cast<float>(bucketArray.size())].push_back(value);
|
||
|
|
}
|
||
|
|
|
||
|
|
// Track the last used index in the final sorted array; Starting at 0
|
||
|
|
int currentIndex = 0;
|
||
|
|
// Sort each bucket in the bucketArray
|
||
|
|
for (std::list<float> &bucket : bucketArray) {
|
||
|
|
bucket.sort();
|
||
|
|
// After sorting each bucket, rewrite values in-order to final sorted array
|
||
|
|
for (const auto &value : bucket) array[currentIndex++] = value;
|
||
|
|
}
|
||
|
|
|
||
|
|
}
|