This program implements merge sort. Merging is the process of combining two or more sorted files into a third sorted file.  
                                  

merge(int a[], int n)
{
        int temp,i ,j,k, l1, l2, size, u1, u2;
        size =1;
        while(size < n)
{
        l1 = 0;
        k=0;
        while(l1+size=n)
                u2=n � 1;
        i = l1;
        j = l2;
        while( i<=u1 && j <= u2)
                if (a[i]<=a[j])
                        temp[k++]=a[i++];
                else
        temp[k++]=a[j++];
while( i<=u1)
                        temp[k++]=a[i++];
while( j<=u2)
                        temp[k++]=a[j++];
        l1 = u2 +1;
}
for( i=l1;k