added code for Bitcoin sort in java

Java/BitcoinSort.java

@@ -0,0 +1,86 @@
+/* Java program for Bitonic Sort. Note that this program
+works only when size of input is a power of 2. */
+public class BitonicSort
+{
+	/* The parameter dir indicates the sorting direction,
+	ASCENDING or DESCENDING; if (a[i] > a[j]) agrees
+	with the direction, then a[i] and a[j] are
+	interchanged. */
+	void compAndSwap(int a[], int i, int j, int dir)
+	{
+		if ( (a[i] > a[j] && dir == 1) ||
+			(a[i] < a[j] && dir == 0))
+		{
+			// Swapping elements
+			int temp = a[i];
+			a[i] = a[j];
+			a[j] = temp;
+		}
+	}
+
+	/* It recursively sorts a bitonic sequence in ascending
+	order, if dir = 1, and in descending order otherwise
+	(means dir=0). The sequence to be sorted starts at
+	index position low, the parameter cnt is the number
+	of elements to be sorted.*/
+	void bitonicMerge(int a[], int low, int cnt, int dir)
+	{
+		if (cnt>1)
+		{
+			int k = cnt/2;
+			for (int i=low; i<low+k; i++)
+				compAndSwap(a,i, i+k, dir);
+			bitonicMerge(a,low, k, dir);
+			bitonicMerge(a,low+k, k, dir);
+		}
+	}
+
+	/* This function first produces a bitonic sequence by
+	recursively sorting its two halves in opposite sorting
+	orders, and then calls bitonicMerge to make them in
+	the same order */
+	void bitonicSort(int a[], int low, int cnt, int dir)
+	{
+		if (cnt>1)
+		{
+			int k = cnt/2;
+
+			// sort in ascending order since dir here is 1
+			bitonicSort(a, low, k, 1);
+
+			// sort in descending order since dir here is 0
+			bitonicSort(a,low+k, k, 0);
+
+			// Will merge whole sequence in ascending order
+			// since dir=1.
+			bitonicMerge(a, low, cnt, dir);
+		}
+	}
+
+	/*Caller of bitonicSort for sorting the entire array
+	of length N in ASCENDING order */
+	void sort(int a[], int N, int up)
+	{
+		bitonicSort(a, 0, N, up);
+	}
+
+	/* A utility function to print array of size n */
+	static void printArray(int arr[])
+	{
+		int n = arr.length;
+		for (int i=0; i<n; ++i)
+			System.out.print(arr[i] + " ");
+		System.out.println();
+	}
+
+	// Driver method
+	public static void main(String args[])
+	{
+		int a[] = {3, 7, 4, 8, 6, 2, 1, 5};
+		int up = 1;
+		BitonicSort ob = new BitonicSort();
+		ob.sort(a, a.length,up);
+		System.out.println("\nSorted array");
+		printArray(a);
+	}
+}