abstract class SortAlgorithm {    
    abstract void sort(int a[]);
        
    public void setParent(SortApplet s) { parent = s; }
        
    public void pause() { parent.pause(100); } 
    
    public void swap(int a[], int i, int j)
       { int T = a[i]; a[i] = a[j]; a[j] = T; }
        
    private SortApplet parent; 
}