อัลกอริธึมการเรียงลำดับที่เก็บข้อมูล (Java, Python, ค/C++ Code ตัวอย่าง)

Start
Create N empty buckets
For each array element:
    Calculate bucket index
    Put that element into the corresponding bucket
For each bucket:
    Sort elements within each bucket
Merge all the elements from each bucket
Output the sorted array
End

//Bucket Sort Program in C/C++
//For values without integer parts
#include <bits/stdc++.h>
#define BUCKET_SIZE 10
using namespace std;
void bucketSort(float input[], int array_size)
{
  vector <float>bucket[BUCKET_SIZE];
  for (int i = 0; i < array_size; i++) {
    int index = BUCKET_SIZE*input[i];
    bucket[index].push_back(input[i]);
  }
  for (int i = 0; i < BUCKET_SIZE; i++)
    sort(bucket[i].begin(), bucket[i].end());
  int out_index = 0;
  for (int i = 0; i < BUCKET_SIZE; i++)
    for (int j = 0; j < bucket[i].size(); j++)
      input[out_index++] = bucket[i][j];
}
int main()
{
  float input[]={0.78,0.17,0.39,0.26,0.72,0.94,0.21,0.12,0.23,0.69};
  int array_size = sizeof(input)/sizeof(input[0]);

  bucketSort(input, array_size);
  cout <<"Sorted Output: 
";
  for (int i = 0; i< array_size; i++)
    cout<<input[i]<<" ";
  return 0;
}

Sorted Output:
0.12 0.17 0.21 0.23 0.26 0.39 0.69 0.72 0.78 0.94

# Bucket Sort Program in Python
# For values without integer parts
def bucketSort(input):
    output = []
    bucket_size = 10
    for bucket in range(bucket_size):
        output.append([])
    for element in input:
        index = int(bucket_size * element)
        output[index].append(element)
    for bucket in range(bucket_size):
        output[bucket] = sorted(output[bucket])
    out_index = 0
    for bucket in range(bucket_size):
        for element in range(len(output[bucket])):
            input[out_index] = output[bucket][element]
            out_index += 1
    return input

input = [0.78, 0.17, 0.39, 0.26, 0.72, 0.94, 0.21, 0.12, 0.23, 0.69]
print("Sorted Output:")
print(bucketSort(input))

Sorted Output:
[0.12, 0.17, 0.21, 0.23, 0.26, 0.39, 0.69, 0.72, 0.78, 0.94]

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
public class BucketSort {
    private static final int BUCKET_SIZE = 10;
    public static void bucketSort(float[] input, int arraySize) {
        List<Float>[] bucket = new ArrayList[BUCKET_SIZE];
        for (int i = 0; i < arraySize; i++) {
            int index = (int)(BUCKET_SIZE * input[i]);
            if (bucket[index] == null) {
                bucket[index] = new ArrayList<>();
            }
            bucket[index].add(input[i]);
        }
        for (int i = 0; i < BUCKET_SIZE; i++) {
            if (bucket[i] != null) {
                Collections.sort(bucket[i]);
            }
        }
        int outIndex = 0;
        for (int i = 0; i < BUCKET_SIZE; i++) {
            if (bucket[i] != null) {
                for (float value: bucket[i]) {
                    input[outIndex++] = value;
                }
            }
        }
    }
    public static void main(String[] args) {
        float[] input = {0.78f,0.17f,0.39f,0.26f,0.72f,0.94f,0.21f,0.12f,0.23f,0.69f};
        int arraySize = input.length;
        bucketSort(input, arraySize);
        System.out.println("Sorted Output:");
        for (int i = 0; i < arraySize; i++) {
            System.out.print(input[i]+" ");
        }
    }
}

Sorted Output:
0.12 0.17 0.21 0.23 0.26 0.39 0.69 0.72 0.78 0.94

#include<bits/stdc++.h>
using namespace std;
void bucketSort(vector < double > & input, int No_Of_Buckets)
{
  double max_value = * max_element(input.begin(), input.end());
  double min_value = * min_element(input.begin(), input.end());
  double span = (max_value - min_value) / No_Of_Buckets;
  vector<vector <double>> output;
  for (int i = 0; i < No_Of_Buckets; i++)
    output.push_back(vector <double>());
  for (int i = 0; i < input.size(); i++)
  {
    double difference = (input[i] - min_value) / span
     - int((input[i] - min_value) / span);
    if (difference == 0 && input[i] != min_value)
      output[int((input[i] - min_value) / span) - 1].push_back(input[i]);
    else
      output[int((input[i] - min_value) / span)].push_back(input[i]);
  }
  for (int i = 0; i < output.size(); i++)
  {
    if (!output[i].empty())
      sort(output[i].begin(), output[i].end());
  }
  int index = 0;
  for (vector <double> & bucket: output)
  {
    if (!bucket.empty())
    {
      for (double i: bucket)
      {
        input[index] = i;
        index++;
      }
    }
  }
}
int main()
{
  vector <double> input ={11,9,21,8,17,19,13,1,24,12};
  int No_Of_Buckets = 5;
  bucketSort(input, No_Of_Buckets);
  cout<<"Sorted Output:";
  for (int i=0; i < input.size(); i++)
    cout <<input[i]<<" ";
  return 0;
}

Sorted Output:1 8 9 11 12 13 17 19 21 24

def bucketSort(input, No_Of_Buckets):
    max_element = max(input)
    min_element = min(input)
    span = (max_element - min_element) / No_Of_Buckets
    output = []
    for bucket in range(No_Of_Buckets):
        output.append([])
    for element in range(len(input)):
        diff = (input[element] - min_element) / span - int(
            (input[element] - min_element) / span
        )
        if diff == 0 and input[element] != min_element:
            output[int((input[element] - min_element) / span) - 1].append(
                input[element]
            )
        else:
            output[int((input[element] - min_element) / span)].append(input[element])
    for bucket in range(len(output)):
        if len(output[bucket]) != 0:
            output[bucket].sort()
    index = 0
    for bucket in output:
        if bucket:
            for element in bucket:
                input[index] = element
                index = index + 1
input = [11, 9, 21, 8, 17, 19, 13, 1, 24, 12]
No_Of_Buckets = 5
bucketSort(input, No_Of_Buckets)
print("Sorted Output:
", input)

Sorted Output:
[1, 8, 9, 11, 12, 13, 17, 19, 21, 24]

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
public class BucketSort {
    public static void bucketSort(List < Double > input, int No_Of_Buckets) {
        double max_value = Collections.max(input);
        double min_value = Collections.min(input);
        double span =(max_value - min_value) / No_Of_Buckets;
        List<List<Double>> output = new ArrayList<>();
        for (int i = 0; i < No_Of_Buckets; i++) {
            output.add(new ArrayList<>());
        }
        for (Double value: input) {
            double difference = (value - min_value) / span - ((value - min_value) / span);
            if (difference == 0 && value != min_value) {
                output.get((int)((value - min_value) / span) - 1).add(value);
            } else {
                output.get((int)((value - min_value) / span)).add(value);
            }
        }
        for (List <Double> bucket: output) {
            if (!bucket.isEmpty()) {
                Collections.sort(bucket);
            }
        }
        int index = 0;
        for (List <Double> bucket: output) {
            if (!bucket.isEmpty()) {
                for (Double value: bucket) {
                    input.set(index,value);
                    index++;
                }
            }
        }
    }
    public static void main(String[] args) {
        List <Double> input = new ArrayList<>();
        input.add(11.0);
        input.add(9.0);
        input.add(21.0);
        input.add(8.0);
        input.add(17.0);
        input.add(19.0);
        input.add(13.0);
        input.add(1.0);
        input.add(24.0);
        input.add(12.0);
        int No_Of_Buckets = 5;
        bucketSort(input, No_Of_Buckets);
        System.out.println("Sorted Output:");
        for (Double value: input) {
            System.out.print(value + " ");
        }
    }
}

Sorted Output:
1.0 8.0 9.0 11.0 12.0 13.0 17.0 19.0 21.0 24.0