mergeSort.java

public class mergeSort {

    /**
     * @param args
     */
    public static void main(String a[])
    {
        int i;
        int array[] = {12,9,4,99,120,1,3,10};
        System.out.println(" Merge Sort\n\n");
        System.out.println("Values Before the sort:\n");
        for(i = 0; i < array.length; i++)
            System.out.print( array[i]+"  ");
        System.out.println();
        mergeSort_srt(array,0, array.length-1);
        System.out.print("Values after the sort:\n");
        for(i = 0; i <array.length; i++)
            System.out.print(array[i]+"  ");
        System.out.println();
        System.out.println("PAUSE");
    }

    public static void mergeSort_srt(int array[],int lo, int n)
    {
        int low = lo;
        int high = n;
        if (low >= high)
        {
            return;
        }
        int middle = (low + high) / 2;
        mergeSort_srt(array, low, middle);
        mergeSort_srt(array, middle + 1, high);
        int end_low = middle;
        int start_high = middle + 1;
        while ((lo <= end_low) && (start_high <= high))
        {
            if (array[low] < array[start_high])
            {
                low++;
            }
            else
            {
                int Temp = array[start_high];
                for (int k = start_high- 1; k >= low; k--)
                {
                    array[k+1] = array[k];
                }
                array[low] = Temp;
                low++;
                end_low++;
                start_high++;
            }
        }
    }
}