Create PigeonholeSort.java

Author: diwakar1593

PigeonholeSort.java

@@ -0,0 +1,54 @@
+/* Java program to implement Pigeonhole Sort */
+
+import java.lang.*;
+import java.util.*;
+
+public class PigeonholeSort
+{
+	public static void pigeonhole_sort(int arr[],
+										int n)
+	{
+		int min = arr[0];
+		int max = arr[0];
+		int range, i, j, index; 
+
+		for(int a=0; a<n; a++)
+		{
+			if(arr[a] > max)
+				max = arr[a];
+			if(arr[a] < min)
+				min = arr[a];
+		}
+
+		range = max - min + 1;
+		int[] phole = new int[range];
+		Arrays.fill(phole, 0);
+
+		for(i = 0; i<n; i++)
+			phole[arr[i] - min]++;
+
+		
+		index = 0;
+
+		for(j = 0; j<range; j++)
+			while(phole[j]-->0)
+				arr[index++]=j+min;
+
+	}
+
+	public static void main(String[] args)
+	{
+		PigeonholeSort sort = new PigeonholeSort();
+		int[] arr = {8, 3, 2, 7, 4, 6, 8};
+
+		System.out.print("Sorted order is : ");
+
+		sort.pigeonhole_sort(arr,arr.length);
+		
+		for(int i=0 ; i<arr.length ; i++)
+			System.out.print(arr[i] + " ");
+	}
+
+}
+
+