This is a Java Program to implement Counting Sort Algorithm. This program is to sort a list of numbers.

Here is the source code of the Java program to implement Counting Sort Algorithm. The Java program is successfully compiled and run on a Windows system. The program output is also shown below.

Here is the source code of the Java program to implement Counting Sort Algorithm. The Java program is successfully compiled and run on a Windows system. The program output is also shown below.

`/**`

`** Java Program to Implement Counting Sort`

`**/`

import java.util.Scanner;

`/** Class CountingSort **/`

public class CountingSort

`{`

private static final int MAX_RANGE = 1000000;

`/** Counting Sort function **/`

public static void sort( int[] arr )

`{`

int N = arr.length;

if (N == 0)

return;

`/** find max and min values **/`

int max = arr[0], min = arr[0];

for (int i = 1; i < N; i++)

`{`

if (arr[i] > max)

max = arr[i];

if (arr[i] < min)

min = arr[i];

`}`

int range = max - min + 1;

`/** check if range is small enough for count array **/`

`/** else it might give out of memory exception while allocating memory for array **/`

if (range > MAX_RANGE)

`{`

System.out.println("\nError : Range too large for sort");

return;

`}`

int[] count = new int[range];

`/** make count/frequency array for each element **/`

for (int i = 0; i < N; i++)

count[arr[i] - min]++;

`/** modify count so that positions in final array is obtained **/`

for (int i = 1; i < range; i++)

count[i] += count[i - 1];

`/** modify original array **/`

int j = 0;

for (int i = 0; i < range; i++)

while (j < count[i])

arr[j++] = i + min;

`}`

`/** Main method **/`

public static void main(String[] args)

`{`

Scanner scan = new Scanner( System.in );

System.out.println("Counting Sort Test\n");

int n, i;

`/** Accept number of elements **/`

System.out.println("Enter number of integer elements");

n = scan.nextInt();

`/** Create integer array on n elements **/`

int arr[] = new int[ n ];

`/** Accept elements **/`

System.out.println("\nEnter "+ n +" integer elements");

for (i = 0; i < n; i++)

arr[i] = scan.nextInt();

`/** Call method sort **/`

sort(arr);

`/** Print sorted Array **/`

System.out.println("\nElements after sorting ");

for (i = 0; i < n; i++)

System.out.print(arr[i]+" ");

System.out.println();

`}`

`}`

Counting Sort Test Enter number of integer elements 20 Enter 20 integer elements 54 67 13 24 76 37 97 10 67 24 6 28 5 19 63 1 71 83 97 24 Elements after sorting 1 5 6 10 13 19 24 24 24 28 37 54 63 67 67 71 76 83 97 97

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