/**
 * A shell sort demonstration algorithm
 */
class SS extends SortAlgorithm {
    void sort(int a[]) throws Exception {
        int n = a.length;
	int incr = n/2;
	while (incr >= 1) {
	   for (int i = incr; i<n; i++) {
		if (stopRequested) {
		    return;
		}
		int T = a[i];
		int j = i;
		while ((j >= incr) && (T < a[j-incr])) {
		   a[j] = a[j-incr];
		   j -= incr;
		}
		a[j] = T;
		pause(j,i,i,j);
	   }
	   incr /= 2;
        }
    }
}