import java.io.*; import java.util.*; import java.awt.*; class Dot { int level; // 0 is top, 1 is next, etc. int indent; // 0 is leftmost, 1 is next, etc. float left; // pixels in from left float top; // pixels in from top Dot leftTree; Dot rightTree; int number; Dot shadow; Color color; public Dot(int n, Color clr) { number = n; color = clr; leftTree = null; rightTree = null; shadow = null; } int numberOf() { return number; } float setLeft(float lf) { return left = lf; } float setTop(float tp) { return top = tp; } void setLevel(int lv) { level = lv; } void setIndent(int in) { indent = in; } void setShadow(Dot d) { shadow = d; } void setNumber(int n) { number = n; } void setLefttree (Dot lt) { leftTree = lt; lt.setIndent(2*indent); lt.setLevel(level+1); } void setLeftTree (Dot lt) { leftTree = lt; } void setRightTree (Dot rt) { rightTree = rt; } void setRighttree (Dot rt) { rightTree = rt; rt.setIndent(2*indent+1); rt.setLevel(level+1); } void setColor(Color c) { color = c; } Dot shadowOf() { return shadow; } Dot rightTreeOf() { return rightTree; } Dot leftTreeOf() { return leftTree; } float leftOf() { return left; } float topOf() { return top; } int levelOf() { return level; } int indentOf() { return indent; } Color colorOf() { return color; } } class DotPanel extends Panel implements Runnable { RB graph; Thread relaxer; Dot pick; Dot deletingNode; Color deletingSaveColor; boolean deleteNode = false, removingNode = false; DotPanel(RB graph) { this.graph = graph; } public void run() { while (true) { repaint(); try { Thread.sleep(100 + graph.getNDots()); } catch (InterruptedException e) { break; } } } Image offscreen; Dimension offscreensize; Graphics offgraphics; int left (Dot dot) { Dimension d = size(); double wid = (double)d.width/(1+(1 << dot.levelOf())); return (int)(wid*(dot.indentOf()+1)) + 15; } int top(Dot dot) { return 20+dot.levelOf()*50 + 15; } int offset = 28; public void paintDot(Graphics g, Dot dot, FontMetrics fm, int ox, int oy) { if (dot == null) return; int x = left(dot); int y = top(dot); int tx = (int)dot.leftOf(); int ty = (int)dot.topOf(); String lbl = String.valueOf(dot.numberOf()); int w = fm.stringWidth(lbl); int h = fm.getHeight(); g.setColor(dot.colorOf()); g.fillOval(tx+ox-offset, ty+oy, 30, 30); g.setColor(Color.white); g.drawString(lbl, tx+ox-offset-w/2+15, ty+oy+12+h/2); dot.setLeft((float)(.75*(dot.leftOf()-x) + x)); dot.setTop((float)(.75*(dot.topOf()-y) + y)); } public void paintPickedDot(Graphics g, Dot dot, FontMetrics fm) { if (dot == null) return; int tx = (int)dot.leftOf(); int ty = (int)dot.topOf(); String lbl = String.valueOf(dot.numberOf()); int w = fm.stringWidth(lbl); int h = fm.getHeight(); g.setColor(dot.colorOf()); g.fillOval(tx-offset, ty, 30, 30); g.setColor(Color.white); g.drawString(lbl, tx-offset-w/2+15, ty+12+h/2); } public void paintEdgesOfDot(Graphics g, Dot dot) { if (dot == null) return; g.setColor(Color.black); int x = (int)dot.leftOf()+15; int y = (int)dot.topOf()+15; if (dot.leftTreeOf() != null) { int lx = (int)dot.leftTreeOf().leftOf()+15; int ly = (int)dot.leftTreeOf().topOf()+15; g.drawLine(x-offset,y,lx-offset,ly); } if (dot.rightTreeOf() != null) { int rx = (int)dot.rightTreeOf().leftOf()+15; int ry = (int)dot.rightTreeOf().topOf()+15; g.drawLine(x-offset,y,rx-offset,ry); } } public void update(Graphics g) { Dimension d = size(); if ((offscreen == null) || (d.width != offscreensize.width) || (d.height != offscreensize.height)) { offscreen = createImage(d.width, d.height); offscreensize = d; offgraphics = offscreen.getGraphics(); offgraphics.setFont(getFont()); } offgraphics.setColor(graph.getColor()); offgraphics.fillRect(0, 0, d.width, d.height); FontMetrics fm = offgraphics.getFontMetrics(); Dot dt[] = graph.getDots(); int nd = graph.getNDots(); for (int i=0 ; i < nd ; i++) paintEdgesOfDot(offgraphics, dt[i]); for (int i=0 ; i < nd ; i++) if (dt[i] != pick) paintDot(offgraphics, dt[i], fm, 0, 0); else paintPickedDot(offgraphics, dt[i], fm); if (graph.getNewest() != null) paintDot(offgraphics, graph.getNewest(), fm, -30, -15); g.drawImage(offscreen, 0, 0, null); } public boolean mouseDown(Event evt, int x, int y) { Dot dot[] = graph.getDots(); for (int i=0 ; i < graph.getNDots() ; i++) { if (dot[i] == null) continue; if (x-dot[i].leftOf() < 0 && y-dot[i].topOf() < 30 && x > dot[i].leftOf()-30 && y > dot[i].topOf()) { pick = dot[i]; if (deleteNode == true) { deleteNode = false; deletingNode = pick; deletingSaveColor = deletingNode.colorOf(); deletingNode.setColor(Color.green); removingNode = true; } return true; } } return true; } public boolean mouseDrag(Event evt, int x, int y) { if (pick != null) { pick.setLeft(x+20); pick.setTop(y-10); } return true; } public boolean mouseUp(Event evt, int x, int y) { pick = null; return true; } public void start() { relaxer = new Thread(this); relaxer.start(); } public void stop() { relaxer.stop(); } public void setValue(boolean v) { deleteNode = v; } public boolean removingOf() { return removingNode; } public Dot dotOf() { return deletingNode; } public Color saveColorOf() { return deletingSaveColor; } public void setRemoving(boolean v) { removingNode = v; } } public class RB extends java.applet.Applet { DotPanel panel; Dot shadow; int sysLock = 0; Dot cdot[] = new Dot[100]; int cndots = 0; Dot dot[] = new Dot[100]; int ndots = 0; Dot ss[] = new Dot[100]; Dot rev1 = null, rev2 = null, rev3 = null; int ssindex = 0; Dot head = null; Dot chead = null; Dot temp = null; Dot newest = null; Dot stopdot = new Dot(0, Color.black); Dot pushdownward; Dot pushupward; Dot t_dot; Button addbutton,nextbutton,undobutton,startbutton,tempbutton,delbutton; TextField val; Panel p; Color bgcolor = new Color(190,190,190); Color downSaveColor; int step = 0; boolean inserting = false; Dot[] getDots() { return dot; } int getNDots() { return ndots; } Dot getNewest() { return newest; } Color getColor() { if (rev1 == null && rev2 == null && rev3 == null && !panel.removingOf() && temp == null && !(head == null && newest != null) && ssindex == 0 && (head != null && head.colorOf() == Color.black)) { bgcolor = new Color(190,190,190); inserting = false; } else if (panel.removingOf()) bgcolor = new Color(0,190,190); return bgcolor; } public void init() { setLayout(new BorderLayout()); panel = new DotPanel(this); add("Center", panel); p = new Panel(); add("South", p); p.add(startbutton = new Button("Restart")); p.add(undobutton = new Button("Undo")); p.add(val = new TextField(5)); p.add(addbutton = new Button("Add Node")); p.add(nextbutton = new Button("Next Step")); p.add(delbutton = new Button("Delete Node")); } public void start() { panel.start(); } public void stop() { panel.stop(); } Dot copyTree(Dot root) { if (root == null) return null; Dot dot = new Dot(root.numberOf(), root.colorOf()); dot.setTop(root.topOf()); dot.setLeft(root.leftOf()); dot.setLevel(root.levelOf()); dot.setIndent(root.indentOf()); dot.setLeftTree(copyTree(root.leftTreeOf())); dot.setRightTree(copyTree(root.rightTreeOf())); root.setShadow(dot); return dot; } int insertCopy(Dot root, Dot p[], int ss) { if (root == null) return ss; p[ss++] = root; ss = insertCopy(root.leftTreeOf(), p, ss); ss = insertCopy(root.rightTreeOf(), p, ss); return ss; } void reLevel(Dot dot, int ind, int lvl) { if (dot == null) return; dot.setLevel(lvl); dot.setIndent(ind); reLevel(dot.leftTreeOf(), 2*ind, lvl+1); reLevel(dot.rightTreeOf(), 2*ind+1 , lvl+1); } void leftRotate(Dot chld, Dot prnt) { prnt.setLeftTree(chld.rightTreeOf()); chld.setRightTree(prnt.leftTreeOf().leftTreeOf()); prnt.leftTreeOf().setLeftTree(chld); reLevel(head, 0, 0); } void srightRotate(Dot chld, Dot prnt) { prnt.setRightTree(chld.leftTreeOf()); chld.setLeftTree(prnt.rightTreeOf().rightTreeOf()); prnt.rightTreeOf().setRightTree(chld); reLevel(head, 0, 0); } void rightRotate(Dot chld, Dot prnt) { prnt.setLeftTree(chld.leftTreeOf()); chld.setLeftTree(prnt.leftTreeOf().rightTreeOf()); prnt.leftTreeOf().setRightTree(chld); reLevel(head, 0, 0); } void sleftRotate(Dot chld, Dot prnt) { prnt.setRightTree(chld.rightTreeOf()); chld.setRightTree(prnt.rightTreeOf().leftTreeOf()); prnt.rightTreeOf().setLeftTree(chld); reLevel(head, 0, 0); } void rightRotate(Dot dot) { head = dot.leftTreeOf(); dot.setLeftTree(head.rightTreeOf()); head.setRightTree(dot); reLevel(head, 0, 0); } void sleftRotate(Dot dot) { head = dot.rightTreeOf(); dot.setRightTree(head.leftTreeOf()); head.setLeftTree(dot); reLevel(head, 0, 0); } int upward() { if (ssindex > 0) { if (ss[ssindex-1].colorOf() == Color.red && ss[ssindex].colorOf() == Color.red) { if (ssindex > 1 && ss[ssindex] == ss[ssindex-1].leftTreeOf() && ss[ssindex-1] == ss[ssindex-2].leftTreeOf()) { if (ss[ssindex-2].rightTreeOf() == null || ss[ssindex-2].rightTreeOf().colorOf() == Color.black) { if (ssindex > 2) { if (ss[ssindex-3].leftTreeOf() == ss[ssindex-2]) rightRotate(ss[ssindex-2], ss[ssindex-3]); else srightRotate(ss[ssindex-2], ss[ssindex-3]); play(getCodeBase(), "audio/ah.au"); rev1 = ss[ssindex-1]; rev2 = ss[ssindex-2]; ss[ssindex-2] = ss[ssindex-1]; ssindex -= 2; return 1; } else { rightRotate(ss[ssindex-2]); play(getCodeBase(), "audio/ooh.au"); rev1 = head; rev2 = head.rightTreeOf(); ssindex = 0; return 1; } } else { rev1 = ss[ssindex-2]; rev2 = ss[ssindex-2].leftTreeOf(); rev3 = ss[ssindex-2].rightTreeOf(); ssindex -= 2; return 2; } } else if (ssindex > 1 && ss[ssindex] == ss[ssindex-1].rightTreeOf() && ss[ssindex-1] == ss[ssindex-2].leftTreeOf()) { if (ss[ssindex-2].rightTreeOf() == null || ss[ssindex-2].rightTreeOf().colorOf() == Color.black) { leftRotate(ss[ssindex-1], ss[ssindex-2]); play(getCodeBase(), "audio/ah.au"); Dot tt = ss[ssindex]; ss[ssindex] = ss[ssindex-1]; ss[ssindex-1] = tt; return 1; } else { rev1 = ss[ssindex-2]; rev2 = ss[ssindex-2].leftTreeOf(); rev3 = ss[ssindex-2].rightTreeOf(); ssindex -= 2; return 2; } } else if (ssindex > 1 && ss[ssindex] == ss[ssindex-1].rightTreeOf() && ss[ssindex-1] == ss[ssindex-2].rightTreeOf()) { if (ss[ssindex-2].leftTreeOf() == null || ss[ssindex-2].leftTreeOf().colorOf() == Color.black) { if (ssindex > 2) { if (ss[ssindex-3].rightTreeOf() == ss[ssindex-2]) sleftRotate(ss[ssindex-2], ss[ssindex-3]); else leftRotate(ss[ssindex-2], ss[ssindex-3]); play(getCodeBase(), "audio/ooh.au"); rev1 = ss[ssindex-1]; rev2 = ss[ssindex-2]; ss[ssindex-2] = ss[ssindex-1]; ssindex -= 2; return 1; } else { sleftRotate(ss[ssindex-2]); play(getCodeBase(), "audio/ooh.au"); rev1 = head; rev2 = head.leftTreeOf(); ssindex = 0; return 1; } } else { rev1 = ss[ssindex-2]; rev2 = ss[ssindex-2].leftTreeOf(); rev3 = ss[ssindex-2].rightTreeOf(); ssindex -= 2; return 2; } } else if (ssindex > 1 && ss[ssindex] == ss[ssindex-1].leftTreeOf() && ss[ssindex-1] == ss[ssindex-2].rightTreeOf()) { if (ss[ssindex-2].leftTreeOf() == null || ss[ssindex-2].leftTreeOf().colorOf() == Color.black) { srightRotate(ss[ssindex-1], ss[ssindex-2]); play(getCodeBase(), "audio/ah.au"); Dot tt = ss[ssindex]; ss[ssindex] = ss[ssindex-1]; ss[ssindex-1] = tt; return 1; } else { rev1 = ss[ssindex-2]; rev2 = ss[ssindex-2].leftTreeOf(); rev3 = ss[ssindex-2].rightTreeOf(); ssindex -= 2; return 2; } } } else { return 0; } } return 0; } Dot insertDot(Dot dot, Dot root) { if (root == null) return null; if (dot.numberOf() == root.numberOf()) { play(getCodeBase(), "audio/drip.au"); ssindex = 0; return newest = temp = null; } else if (dot.numberOf() < root.numberOf()) { dot.setLevel(root.levelOf()+1); dot.setIndent(2*root.indentOf()); if (root.leftTreeOf() == null) { stopdot.setColor(Color.green); return stopdot; } return root.leftTreeOf(); } else { dot.setLevel(root.levelOf()+1); dot.setIndent(2*root.indentOf()+1); if (root.rightTreeOf() == null) { stopdot.setColor(Color.yellow); return stopdot; } return root.rightTreeOf(); } } Dot reverseColor(Dot dot) { if (dot.colorOf() == Color.black) dot.setColor(Color.red); else if (dot.colorOf() == Color.red) dot.setColor(Color.black); return null; } void deleteDot(Dot d) { int m; for (int k=0 ; k < ndots ; k++) { if (dot[k] == null) continue; if (dot[k] == d) { dot[k] = null; break; } } for (int k=0 ; k < ndots ; k++) { if (dot[k] == null) continue; if (dot[k].leftTreeOf() == d) { dot[k].setLeftTree(null); break; } if (dot[k].rightTreeOf() == d) { dot[k].setRightTree(null); break; } } for (int k=0 ; k < ndots ; k++) if (dot[k] != null) return; head = null; return; } Dot parentOf(Dot d) { for (int k=0 ; k < ndots ; k++) { if (dot[k] == null) continue; if (dot[k].leftTreeOf() == d) return dot[k]; if (dot[k].rightTreeOf() == d) return dot[k]; } return null; } public boolean action(Event evt, Object arg) { if (evt.target.equals(startbutton)) { ndots = cndots = ssindex = 0; head = chead = rev1 = rev2 = rev3 = newest = temp = null; for (int i=0 ; i < 100 ; i++) { dot[i] = cdot[i] = ss[i] = null; } bgcolor = new Color(190, 190, 190); inserting = false; return super.action(evt, arg); } else if (evt.target.equals(undobutton)) { if (panel.removingOf()) return super.action(evt, arg); if (chead == null) return super.action(evt, arg); for (int i=0 ; i < ndots ; i++) { if (dot[i] == null) continue; if ((shadow = dot[i].shadowOf()) != null) { shadow.setLeft(dot[i].leftOf()); shadow.setTop(dot[i].topOf()); } } for (int i=0 ; i < cndots ; i++) { dot[i] = cdot[i]; ss[i] = null; } ndots = cndots; head = chead; chead = null; rev1 = rev2 = rev3 = newest = temp = null; ssindex = 0; return super.action(evt, arg); } else if (evt.target.equals(addbutton)) { if (rev1 != null || rev2 != null || rev3 != null || temp != null || (head == null && newest != null) || ssindex != 0 || (head != null && head.colorOf() != Color.black)) { play(getCodeBase(), "audio/ooh.au"); } else if (newest == null && !panel.removingOf()) { int num = 0; inserting = true; ndots = insertCopy(head = copyTree(head), dot, 0); /* try it */ cndots = insertCopy(chead = copyTree(head), cdot, 0); ssindex = 0; try { num = Integer.parseInt(val.getText()); } catch (NumberFormatException e) { return super.action(evt, arg); } newest = new Dot(num, Color.red); newest.setLevel(0); newest.setIndent(0); temp = head; bgcolor = new Color(0,190,190); } return super.action(evt, arg); } else if (evt.target.equals(nextbutton)) { if (panel.removingOf() && head != null) // deleting a node { if (step == 0) // beginning to go down; { if (panel.dotOf().leftTreeOf() != null && panel.dotOf().rightTreeOf() != null) // both children there { Dot P = parentOf(panel.dotOf()); Dot A = panel.dotOf().leftTreeOf(); Dot B = panel.dotOf(); Dot C = panel.dotOf().rightTreeOf(); if (C.leftTreeOf() == null && C.rightTreeOf() == null) { if (A.leftTreeOf() != null && A.rightTreeOf() != null) { if (P != null) { if (P.leftTreeOf() == B) P.setLeftTree(A); else P.setRightTree(A); } else head = A; C.setLeftTree(A.rightTreeOf()); A.setRightTree(C); C.setColor(Color.black); C.leftTreeOf().setColor(Color.red); A.leftTreeOf().setColor(Color.black); if (A.colorOf() == Color.black) A.setColor(Color.red); else A.setColor(Color.black); } else if (A.leftTreeOf() == null && A.rightTreeOf() != null) { Dot E = A.rightTreeOf(); if (P != null) { if (P.leftTreeOf() == B) P.setLeftTree(E); else P.setRightTree(E); } else head = E; E.setLeftTree(A); E.setRightTree(C); A.setRightTree(null); A.setColor(Color.black); C.setColor(Color.black); E.setColor(panel.saveColorOf()); } else if (A.leftTreeOf() != null && A.rightTreeOf() == null) { if (P != null) { if (P.leftTreeOf() == B) P.setLeftTree(A); else P.setRightTree(A); } else head = A; A.setRightTree(C); A.setColor(panel.saveColorOf()); C.setColor(Color.black); A.leftTreeOf().setColor(Color.black); } else if (A.leftTreeOf() == null && A.rightTreeOf() == null) { if (P != null) { if (P.leftTreeOf() == B) P.setLeftTree(A); else P.setRightTree(A); } else head = A; // one black & two reds or three blacks at top if (panel.saveColorOf() == Color.red || P == null) { A.setRightTree(C); A.setColor(Color.black); C.setColor(Color.red); } else // two reds on bottom if (A.colorOf() == Color.red) { A.setRightTree(C); A.setColor(Color.black); } else // triangle of 3 blacks at bottom, not at root { A.setRightTree(C); A.setColor(Color.black); C.setColor(Color.red); if (P != null) { if (P.rightTreeOf() == panel.dotOf()) P.setRightTree(A); else if (P.leftTreeOf() == panel.dotOf()) P.setLeftTree(A); pushupward = A; deleteDot(B); reLevel(head,0,0); panel.setRemoving(true); bgcolor = new Color(0,190,190); step = 2; return super.action(evt, arg); } else head = A; } } deleteDot(B); reLevel(head,0,0); panel.setRemoving(false); bgcolor = new Color(190,190,190); step = 0; } else if (C.leftTreeOf() == null) { if (P != null) { if (P.leftTreeOf() == B) P.setLeftTree(C); else P.setRightTree(C); } else head = C; C.setLeftTree(A); C.setColor(panel.saveColorOf()); C.rightTreeOf().setColor(Color.black); deleteDot(B); reLevel(head,0,0); panel.setRemoving(false); bgcolor = new Color(190,190,190); step = 0; } else { pushdownward = panel.dotOf().rightTreeOf(); downSaveColor = pushdownward.colorOf(); pushdownward.setColor(Color.yellow); step = 1; } } else if (panel.dotOf().leftTreeOf() != null) // only left child { t_dot = parentOf(panel.dotOf()); if (t_dot != null) { if (t_dot.leftTreeOf() == panel.dotOf()) t_dot.setLeftTree(panel.dotOf().leftTreeOf()); else t_dot.setRightTree(panel.dotOf().leftTreeOf()); } else head = panel.dotOf().leftTreeOf(); panel.dotOf().leftTreeOf().setColor(Color.black); deleteDot(panel.dotOf()); reLevel(head,0,0); panel.setRemoving(false); bgcolor = new Color(190,190,190); step = 0; } else if (panel.dotOf().rightTreeOf() != null) // only right child { t_dot = parentOf(panel.dotOf()); if (t_dot != null) { if (t_dot.leftTreeOf() == panel.dotOf()) t_dot.setLeftTree(panel.dotOf().rightTreeOf()); else t_dot.setRightTree(panel.dotOf().rightTreeOf()); } else head = panel.dotOf().rightTreeOf(); panel.dotOf().rightTreeOf().setColor(Color.black); deleteDot(panel.dotOf()); reLevel(head,0,0); panel.setRemoving(false); bgcolor = new Color(190,190,190); step = 0; } else // no children { if (panel.dotOf() == head) { deleteDot(panel.dotOf()); head = null; } else if (parentOf(panel.dotOf()).colorOf() == Color.red) { Dot A,B,C,D,P; int z; Dot parent = parentOf(panel.dotOf()); if (parent.leftTreeOf() == panel.dotOf()) z=0; else z=1; if (z==0 && (parent.rightTreeOf().rightTreeOf() != null && parent.rightTreeOf().leftTreeOf() != null)) { A = parent; B = parent.rightTreeOf(); C = parent.rightTreeOf().leftTreeOf(); D = parent.rightTreeOf().rightTreeOf(); P = parentOf(parent); A.setRightTree(C); A.setLeftTree(null); B.setLeftTree(A); B.setRightTree(D); C.setLeftTree(null); C.setRightTree(null); D.setLeftTree(null); D.setRightTree(null); if (P != null) { if (P.leftTreeOf() == parent) P.setLeftTree(B); else P.setRightTree(B); } else head = B; B.setColor(Color.red); A.setColor(Color.black); D.setColor(Color.black); C.setColor(Color.red); } else if (z==0 && (parent.rightTreeOf().rightTreeOf() == null && parent.rightTreeOf().leftTreeOf() != null)) { A = parent; B = parent.rightTreeOf(); C = parent.rightTreeOf().leftTreeOf(); P = parentOf(parent); A.setRightTree(null); A.setLeftTree(null); B.setLeftTree(null); B.setRightTree(null); C.setLeftTree(A); C.setRightTree(B); if (P != null) { if (P.leftTreeOf() == parent) P.setLeftTree(C); else P.setRightTree(C); } else head = C; B.setColor(Color.black); A.setColor(Color.black); C.setColor(Color.red); } else if (z==0 && (parent.rightTreeOf().rightTreeOf() != null && parent.rightTreeOf().leftTreeOf() == null)) { A = parent; B = parent.rightTreeOf(); D = parent.rightTreeOf().rightTreeOf(); P = parentOf(parent); A.setRightTree(null); A.setLeftTree(null); B.setLeftTree(A); B.setRightTree(D); D.setLeftTree(null); D.setRightTree(null); if (P != null) { if (P.leftTreeOf() == parent) P.setLeftTree(B); else P.setRightTree(B); } else head = B; B.setColor(Color.red); A.setColor(Color.black); D.setColor(Color.black); } else if (z==0 && (parent.rightTreeOf().rightTreeOf() == null && parent.rightTreeOf().leftTreeOf() == null)) { A = parent; B = parent.rightTreeOf(); A.setLeftTree(null); B.setColor(Color.red); A.setColor(Color.black); } else if (z==1 && (parent.leftTreeOf().leftTreeOf() != null && parent.leftTreeOf().rightTreeOf() != null)) { A = parent; B = parent.leftTreeOf(); C = parent.leftTreeOf().rightTreeOf(); D = parent.leftTreeOf().leftTreeOf(); P = parentOf(parent); A.setLeftTree(C); A.setRightTree(null); B.setRightTree(A); B.setLeftTree(D); C.setRightTree(null); C.setLeftTree(null); D.setRightTree(null); D.setLeftTree(null); if (P != null) { if (P.leftTreeOf() == parent) P.setLeftTree(B); else P.setRightTree(B); } else head = B; B.setColor(Color.red); A.setColor(Color.black); D.setColor(Color.black); C.setColor(Color.red); } else if (z==1 && (parent.leftTreeOf().leftTreeOf() == null && parent.leftTreeOf().rightTreeOf() != null)) { A = parent; B = parent.leftTreeOf(); C = parent.leftTreeOf().rightTreeOf(); P = parentOf(parent); A.setLeftTree(null); A.setRightTree(null); B.setRightTree(null); B.setLeftTree(null); C.setRightTree(A); C.setLeftTree(B); if (P != null) { if (P.leftTreeOf() == parent) P.setLeftTree(C); else P.setRightTree(C); } else head = C; B.setColor(Color.black); A.setColor(Color.black); C.setColor(Color.red); } else if (z==1 && (parent.leftTreeOf().leftTreeOf() != null && parent.leftTreeOf().rightTreeOf() == null)) { A = parent; B = parent.leftTreeOf(); D = parent.leftTreeOf().leftTreeOf(); P = parentOf(parent); A.setLeftTree(null); A.setRightTree(null); B.setRightTree(A); B.setLeftTree(D); D.setRightTree(null); D.setLeftTree(null); if (P != null) { if (P.leftTreeOf() == parent) P.setLeftTree(B); else P.setRightTree(B); } else head = B; B.setColor(Color.red); A.setColor(Color.black); D.setColor(Color.black); } else if (z==1 && (parent.leftTreeOf().leftTreeOf() == null && parent.leftTreeOf().rightTreeOf() == null)) { A = parent; B = parent.leftTreeOf(); A.setRightTree(null); B.setColor(Color.red); A.setColor(Color.black); } deleteDot(panel.dotOf()); reLevel(head,0,0); } else if (parentOf(panel.dotOf()).colorOf() == Color.black) { Dot A,B,C,D,P; int z; Dot parent = parentOf(panel.dotOf()); if (parent != null) { if (parent.leftTreeOf() == panel.dotOf()) z = 0; else z = 1; } else z = -1; if (panel.saveColorOf() == Color.red) { if (parent.leftTreeOf() == panel.dotOf()) parent.setLeftTree(null); else parent.setRightTree(null); } else if (z==0 && (parent.rightTreeOf().rightTreeOf() != null && parent.rightTreeOf().leftTreeOf() != null)) { A = parent; B = parent.rightTreeOf(); C = parent.rightTreeOf().leftTreeOf(); D = parent.rightTreeOf().rightTreeOf(); P = parentOf(parent); if (P != null) { if (P.leftTreeOf() == parent) P.setLeftTree(B); else P.setRightTree(B); } else head = B; if (C.leftTreeOf() == null && C.rightTreeOf() == null) { B.setLeftTree(A); A.setRightTree(C); A.setLeftTree(null); B.setColor(Color.black); A.setColor(Color.black); D.setColor(Color.black); C.setColor(Color.red); if (D.leftTreeOf() != null) D.leftTreeOf().setColor(Color.red); if (D.rightTreeOf() != null) D.rightTreeOf().setColor(Color.red); } else if (C.leftTreeOf() == null && C.rightTreeOf() != null) { C.setLeftTree(A); A.setLeftTree(null); A.setRightTree(null); B.setColor(Color.black); C.setColor(Color.black); D.setColor(Color.black); A.setColor(Color.red); C.rightTreeOf().setColor(Color.red); if (D.leftTreeOf() != null) D.leftTreeOf().setColor(Color.red); if (D.rightTreeOf() != null) D.rightTreeOf().setColor(Color.red); } else if (C.leftTreeOf() != null && C.rightTreeOf() == null) { Dot E = C.leftTreeOf(); B.setLeftTree(E); E.setRightTree(C); E.setLeftTree(A); A.setRightTree(null); A.setLeftTree(null); C.setLeftTree(null); C.setRightTree(null); B.setColor(Color.black); E.setColor(Color.black); D.setColor(Color.black); A.setColor(Color.red); C.setColor(Color.red); if (D.leftTreeOf() != null) D.leftTreeOf().setColor(Color.red); if (D.rightTreeOf() != null) D.rightTreeOf().setColor(Color.red); } else { B.leftTreeOf().leftTreeOf().setLeftTree(A); A.setLeftTree(null); A.setRightTree(null); B.setColor(Color.black); C.setColor(Color.red); D.setColor(Color.black); C.leftTreeOf().setColor(Color.black); C.rightTreeOf().setColor(Color.black); if (D.leftTreeOf() != null) D.leftTreeOf().setColor(Color.red); if (D.rightTreeOf() != null) D.rightTreeOf().setColor(Color.red); A.setColor(Color.red); } } else if (z==0 && (parent.rightTreeOf().rightTreeOf() != null && parent.rightTreeOf().leftTreeOf() == null)) { A = parent; B = parent.rightTreeOf(); D = parent.rightTreeOf().rightTreeOf(); P = parentOf(parent); A.setRightTree(null); A.setLeftTree(null); B.setLeftTree(A); B.setRightTree(D); D.setLeftTree(null); D.setRightTree(null); if (P != null) { if (P.leftTreeOf() == parent) P.setLeftTree(B); else P.setRightTree(B); } else head = B; B.setColor(Color.black); A.setColor(Color.black); D.setColor(Color.black); } else if (z==0 && (parent.rightTreeOf().rightTreeOf() == null && parent.rightTreeOf().leftTreeOf() != null)) { A = parent; B = parent.rightTreeOf(); C = parent.rightTreeOf().leftTreeOf(); P = parentOf(parent); A.setRightTree(null); A.setLeftTree(null); B.setLeftTree(null); B.setRightTree(null); C.setLeftTree(A); C.setRightTree(B); if (P != null) { if (P.leftTreeOf() == parent) P.setLeftTree(C); else P.setRightTree(C); } else head = C; B.setColor(Color.black); A.setColor(Color.black); C.setColor(Color.black); } else if (z==1 && (parent.leftTreeOf().leftTreeOf() != null && parent.leftTreeOf().rightTreeOf() != null)) { A = parent; B = parent.leftTreeOf(); C = parent.leftTreeOf().rightTreeOf(); D = parent.leftTreeOf().leftTreeOf(); P = parentOf(parent); if (P != null) { if (P.leftTreeOf() == parent) P.setLeftTree(B); else P.setRightTree(B); } else head = B; if (C.rightTreeOf() == null && C.leftTreeOf() == null) { B.setRightTree(A); A.setLeftTree(C); A.setRightTree(null); B.setColor(Color.black); A.setColor(Color.black); D.setColor(Color.black); C.setColor(Color.red); if (D.rightTreeOf() != null) D.rightTreeOf().setColor(Color.red); if (D.leftTreeOf() != null) D.leftTreeOf().setColor(Color.red); } else if (C.rightTreeOf() == null && C.leftTreeOf() != null) { C.setRightTree(A); A.setRightTree(null); A.setLeftTree(null); B.setColor(Color.black); C.setColor(Color.black); D.setColor(Color.black); A.setColor(Color.red); C.leftTreeOf().setColor(Color.red); if (D.rightTreeOf() != null) D.rightTreeOf().setColor(Color.red); if (D.leftTreeOf() != null) D.leftTreeOf().setColor(Color.red); } else if (C.rightTreeOf() != null && C.leftTreeOf() == null) { Dot E = C.rightTreeOf(); B.setRightTree(E); E.setLeftTree(C); E.setRightTree(A); A.setLeftTree(null); A.setRightTree(null); C.setRightTree(null); C.setLeftTree(null); B.setColor(Color.black); E.setColor(Color.black); D.setColor(Color.black); A.setColor(Color.red); C.setColor(Color.red); if (D.rightTreeOf() != null) D.rightTreeOf().setColor(Color.red); if (D.leftTreeOf() != null) D.leftTreeOf().setColor(Color.red); } else { B.rightTreeOf().rightTreeOf().setRightTree(A); A.setLeftTree(null); A.setRightTree(null); B.setColor(Color.black); C.setColor(Color.red); D.setColor(Color.black); C.rightTreeOf().setColor(Color.black); C.leftTreeOf().setColor(Color.black); if (D.rightTreeOf() != null) D.rightTreeOf().setColor(Color.red); if (D.leftTreeOf() != null) D.leftTreeOf().setColor(Color.red); A.setColor(Color.red); } } else if (z==1 && (parent.leftTreeOf().leftTreeOf() != null && parent.leftTreeOf().rightTreeOf() == null)) { A = parent; B = parent.leftTreeOf(); D = parent.leftTreeOf().leftTreeOf(); P = parentOf(parent); A.setLeftTree(null); A.setRightTree(null); B.setRightTree(A); B.setLeftTree(D); D.setRightTree(null); D.setLeftTree(null); if (P != null) { if (P.leftTreeOf() == parent) P.setLeftTree(B); else P.setRightTree(B); } else head = B; B.setColor(Color.black); A.setColor(Color.black); D.setColor(Color.black); } else if (z==1 && (parent.leftTreeOf().leftTreeOf() == null && parent.leftTreeOf().rightTreeOf() != null)) { A = parent; B = parent.leftTreeOf(); C = parent.leftTreeOf().rightTreeOf(); P = parentOf(parent); A.setLeftTree(null); A.setRightTree(null); B.setRightTree(null); B.setLeftTree(null); C.setRightTree(A); C.setLeftTree(B); if (P != null) { if (P.leftTreeOf() == parent) P.setLeftTree(C); else P.setRightTree(C); } else head = C; B.setColor(Color.black); A.setColor(Color.black); C.setColor(Color.black); } else // triangle of three blacks at root if (parentOf(parent) == null) { head = parent; if (parent.leftTreeOf() == panel.dotOf()) parent.rightTreeOf().setColor(Color.red); else parent.leftTreeOf().setColor(Color.red); } else // There is a triangle of three blacks at bottom { B = parentOf(panel.dotOf()); if (B.rightTreeOf() == panel.dotOf()) B.leftTreeOf().setColor(Color.red); else B.rightTreeOf().setColor(Color.red); pushupward = B; deleteDot(panel.dotOf()); reLevel(head,0,0); panel.setRemoving(true); bgcolor = new Color(0,190,190); step = 2; return super.action(evt, arg); } deleteDot(panel.dotOf()); reLevel(head,0,0); } panel.setRemoving(false); bgcolor = new Color(190,190,190); step = 0; } } else if (step == 1) { pushdownward.setColor(downSaveColor); if (pushdownward.leftTreeOf().leftTreeOf() != null) { pushdownward = pushdownward.leftTreeOf(); downSaveColor = pushdownward.colorOf(); pushdownward.setColor(Color.yellow); step = 1; } else { pushdownward.leftTreeOf().setColor(Color.yellow); step = 3; } } else if (step == 2) // going up with one less black depth on one side { Dot A,B,C,D,E,F,G,P; A = pushupward; P = parentOf(A); if (P == null) { head = A; panel.setRemoving(false); bgcolor = new Color(190,190,190); step = 0; } else { E = parentOf(P); // Grab E here before parent is lost if (P.leftTreeOf() == A) // Rotate { B = P.rightTreeOf(); C = B.leftTreeOf(); D = B.rightTreeOf(); if (D.colorOf() == Color.black && C.colorOf() == Color.red && B.colorOf() == Color.black) { P.setRightTree(C); B.setLeftTree(C.rightTreeOf()); C.setRightTree(B); B.setColor(Color.red); C.setColor(Color.black); reLevel(head,0,0); step = 2; return super.action(evt, arg); } else if (D.colorOf() == Color.black && C.colorOf() == Color.black && B.colorOf() == Color.red) { F = C.leftTreeOf(); G = C.rightTreeOf(); if (F != null && G != null) { if (G.colorOf() == Color.black) { if (E != null) { if (E.leftTreeOf() == P) E.setLeftTree(B); else E.setRightTree(B); } else head = B; B.setLeftTree(P); P.setRightTree(C); B.setColor(Color.black); C.setColor(Color.red); } else { if (E != null) { if (E.leftTreeOf() == P) E.setLeftTree(C); else E.setRightTree(C); } else head = C; C.setLeftTree(P); C.setRightTree(B); B.setLeftTree(G); P.setRightTree(F); if (G.colorOf() == Color.red) { G.setColor(Color.black); } else { B.setColor(Color.black); D.setColor(Color.red); } } reLevel(head,0,0); step = 0; panel.setRemoving(false); bgcolor = new Color(190,190,190); return super.action(evt, arg); } } else { P.setRightTree(C); B.setLeftTree(P); } } else { B = P.leftTreeOf(); C = B.rightTreeOf(); D = B.leftTreeOf(); if (D.colorOf() == Color.black && C.colorOf() == Color.red && B.colorOf() == Color.black) { P.setLeftTree(C); B.setRightTree(C.leftTreeOf()); C.setLeftTree(B); B.setColor(Color.red); C.setColor(Color.black); reLevel(head,0,0); step = 2; return super.action(evt, arg); } else if (D.colorOf() == Color.black && C.colorOf() == Color.black && B.colorOf() == Color.red) { F = C.rightTreeOf(); G = C.leftTreeOf(); if (F != null && G != null) { if (G.colorOf() == Color.black) { if (E != null) { if (E.leftTreeOf() == P) E.setLeftTree(B); else E.setRightTree(B); } else head = B; B.setRightTree(P); P.setLeftTree(C); B.setColor(Color.black); C.setColor(Color.red); } else { if (E != null) { if (E.leftTreeOf() == P) E.setLeftTree(C); else E.setRightTree(C); } else head = C; C.setRightTree(P); C.setLeftTree(B); B.setRightTree(G); P.setLeftTree(F); if (G.colorOf() == Color.red) { G.setColor(Color.black); } else { B.setColor(Color.black); D.setColor(Color.red); } } reLevel(head,0,0); step = 0; panel.setRemoving(false); bgcolor = new Color(190,190,190); return super.action(evt, arg); } } else { P.setLeftTree(C); B.setRightTree(P); } } if (E != null) { if (E.leftTreeOf() == P) E.setLeftTree(B); else E.setRightTree(B); } else head = B; if (P.colorOf() == Color.red) { if (C.colorOf() == Color.red) { if (B != head) B.setColor(Color.red); else B.setColor(Color.black); B.leftTreeOf().setColor(Color.black); B.rightTreeOf().setColor(Color.black); } panel.setRemoving(false); bgcolor = new Color(190,190,190); step = 0; } else { if (B.colorOf() == Color.red) { B.setColor(Color.black); C.setColor(Color.red); panel.setRemoving(false); bgcolor = new Color(190,190,190); step = 0; } else if (D.colorOf() == Color.red) { D.setColor(Color.black); panel.setRemoving(false); bgcolor = new Color(190,190,190); step = 0; } else // case D = B = P = black, C = red already covered { P.setColor(Color.red); if (E == null) { panel.setRemoving(false); bgcolor = new Color(190,190,190); step = 0; } else { pushupward = B; step = 2; } } } } reLevel(head,0,0); } else if (step == 3) { t_dot = pushdownward.leftTreeOf().rightTreeOf(); panel.dotOf().setNumber(pushdownward.leftTreeOf().numberOf()); panel.dotOf().setColor(panel.saveColorOf()); deleteDot(pushdownward.leftTreeOf()); step = 4; } else if (step == 4) { if (t_dot != null) t_dot.setColor(Color.black); else { if (pushdownward.colorOf() == Color.black) { if (pushdownward.rightTreeOf() == null) { pushdownward.setLeftTree(null); } else if (pushdownward.rightTreeOf().colorOf() == Color.red) { Dot P = parentOf(pushdownward); Dot B = pushdownward.rightTreeOf(); Dot A = B.leftTreeOf(); Dot C = B.rightTreeOf(); if (A != null || C != null) { if (P.leftTreeOf() == pushdownward) P.setLeftTree(B); else P.setRightTree(B); if (A.leftTreeOf()==null && A.rightTreeOf()==null) { B.setLeftTree(pushdownward); pushdownward.setRightTree(A); pushdownward.setLeftTree(null); B.setColor(Color.black); pushdownward.setColor(Color.black); C.setColor(Color.black); A.setColor(Color.red); } else if (A.leftTreeOf()==null && A.rightTreeOf()!=null) { A.setLeftTree(pushdownward); pushdownward.setLeftTree(null); pushdownward.setRightTree(null); pushdownward.setColor(Color.red); B.setColor(Color.black); } else if (A.leftTreeOf()!=null && A.rightTreeOf()==null) { Dot E = A.leftTreeOf(); B.setLeftTree(E); E.setLeftTree(pushdownward); E.setRightTree(A); A.setLeftTree(null); A.setRightTree(null); pushdownward.setLeftTree(null); pushdownward.setRightTree(null); E.setColor(Color.red); B.setColor(Color.black); pushdownward.setColor(Color.black); A.setColor(Color.black); } else { Dot E = A.leftTreeOf(); B.setLeftTree(E); E.setLeftTree(pushdownward); E.setRightTree(A); A.setLeftTree(null); pushdownward.setLeftTree(null); pushdownward.setRightTree(null); E.setColor(Color.red); B.setColor(Color.black); pushdownward.setColor(Color.black); A.setColor(Color.black); } } } else if (pushdownward.rightTreeOf().rightTreeOf() != null) { Dot P = parentOf(pushdownward); Dot B = pushdownward.rightTreeOf(); Dot A = B.leftTreeOf(); Dot C = B.rightTreeOf(); if (P.leftTreeOf() == pushdownward) P.setLeftTree(B); else P.setRightTree(B); B.setLeftTree(pushdownward); if (A != null) pushdownward.setRightTree(A); else pushdownward.setRightTree(null); C.setColor(Color.black); if (A != null) A.setColor(Color.red); reLevel(head,0,0); panel.setRemoving(false); bgcolor = new Color(190,190,190); step = 0; return super.action(evt, arg); } else if (pushdownward.rightTreeOf().leftTreeOf() != null) { Dot P = parentOf(pushdownward); Dot B = pushdownward.rightTreeOf(); Dot A = B.leftTreeOf(); if (P.leftTreeOf() == pushdownward) P.setLeftTree(A); else P.setRightTree(A); A.setLeftTree(pushdownward); A.setRightTree(B); pushdownward.setLeftTree(null); pushdownward.setRightTree(null); B.setLeftTree(null); A.setColor(Color.black); B.setColor(Color.black); pushdownward.setColor(Color.black); reLevel(head,0,0); panel.setRemoving(false); bgcolor = new Color(190,190,190); step = 0; return super.action(evt, arg); } else // triangle of three blacks at bottom { pushdownward.rightTreeOf().setColor(Color.red); pushupward = pushdownward; reLevel(head, 0, 0); step = 2; return super.action(evt, arg); } } else // triangle one red, two blacks { Dot C = pushdownward.rightTreeOf(); Dot A = C.rightTreeOf(); Dot B = C.leftTreeOf(); Dot P = parentOf(pushdownward); if (A == null && B == null) { pushdownward.setColor(Color.black); C.setColor(Color.red); } else if (A != null && B == null) { if (P.leftTreeOf() == pushdownward) P.setLeftTree(C); else P.setRightTree(C); C.setLeftTree(pushdownward); pushdownward.setLeftTree(null); pushdownward.setRightTree(null); C.setColor(Color.red); C.leftTreeOf().setColor(Color.black); C.rightTreeOf().setColor(Color.black); reLevel(head,0,0); } else if (A == null && B != null) { if (P.leftTreeOf() == pushdownward) P.setLeftTree(B); else P.setRightTree(B); B.setLeftTree(pushdownward); B.setRightTree(C); pushdownward.setLeftTree(null); pushdownward.setRightTree(null); C.setLeftTree(null); C.setRightTree(null); B.setColor(Color.red); B.leftTreeOf().setColor(Color.black); B.rightTreeOf().setColor(Color.black); reLevel(head,0,0); } else // both A and B are not null { if (P.leftTreeOf() == pushdownward) P.setLeftTree(C); else P.setRightTree(C); pushdownward.setRightTree(B); pushdownward.setLeftTree(null); C.setLeftTree(pushdownward); C.setColor(Color.red); pushdownward.setColor(Color.black); A.setColor(Color.black); B.setColor(Color.red); reLevel(head,0,0); } } } step = 6; } if (step == 6) { if (t_dot != null) pushdownward.setLeftTree(t_dot); // walk up tree from triangle of blacks, possibly reLevel(head,0,0); panel.setRemoving(false); bgcolor = new Color(190,190,190); step = 0; } } else if (rev1 != null || rev2 != null || rev3 != null) { if (rev1 != null) rev1 = reverseColor(rev1); if (rev2 != null) rev2 = reverseColor(rev2); if (rev3 != null) rev3 = reverseColor(rev3); } else if (temp != null) // Insert the dot (way down) { Color leftdot, topdot, rightdot; topdot = temp.colorOf(); if (temp.leftTreeOf() != null) leftdot=temp.leftTreeOf().colorOf(); else leftdot = Color.blue; if (temp.rightTreeOf() != null) rightdot=temp.rightTreeOf().colorOf(); else rightdot = Color.blue; ss[ssindex++] = temp; if ((temp = insertDot(newest, temp)) == stopdot) { if (stopdot.colorOf()==Color.green) { /*** Experimental - to fix non-red/blackness on add ***/ if (rightdot == Color.black) newest.setColor(Color.black); ss[ssindex-1].setLefttree(newest); } else { /*** Experimental - to fix non-red/blackness on add ***/ if (leftdot == Color.black) newest.setColor(Color.black); ss[ssindex-1].setRighttree(newest); } dot[ndots++] = ss[ssindex] = newest; newest = temp = null; play(getCodeBase(), "audio/ooh.au"); } } else if (head == null && newest != null) // Special case - first dot { dot[ndots++] = ss[ssindex] = head = newest; newest.setColor(Color.black); newest = temp = null; play(getCodeBase(), "audio/whoopy.au"); } else if (ssindex > 0) { int tell; if ((tell = upward()) == 2) { if (rev1 != null) rev1 = reverseColor(rev1); if (rev2 != null) rev2 = reverseColor(rev2); if (rev3 != null) rev3 = reverseColor(rev3); } else if (tell == 0 && rev1 == null && rev2 == null && rev3 == null) { play(getCodeBase(), "audio/train.au"); ssindex = 0; } } else if (head != null && head.colorOf() != Color.black) head.setColor(Color.black); if (!panel.removingOf() && rev1 == null && rev2 == null && rev3 == null && temp == null && !(head == null && newest != null) && ssindex == 0 && (head != null && head.colorOf() == Color.black)) { play(getCodeBase(), "audio/train.au"); bgcolor = new Color(190,190,190); inserting = false; } } else if (evt.target.equals(delbutton)) { if (!panel.removingOf() && !inserting && head != null) { panel.setValue(true); cndots = insertCopy(chead = copyTree(head), cdot, 0); bgcolor = new Color(0,190,190); } } return super.action(evt, arg); } }