English
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.*;
public class ple {
static AVLTreeNode root = null;
public static void main(String[] args) throws Exception {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
String line;
StringBuilder sb = new StringBuilder();
int n;
line = br.readLine();
n = Integer.parseInt(line);
List<Rect> list = new ArrayList<Rect>();
for (int i = 0; i < n; i++) {
line = br.readLine();
String[] tab = line.split(" ");
Rect rect = new Rect();
rect.x = Long.parseLong(tab[0]);
rect.width = Long.parseLong(tab[1]) - rect.x;
rect.y = Long.parseLong(tab[2]);
rect.height = Long.parseLong(tab[3]) - rect.y;
rect.number = i + 1;
list.add(rect);
}
list = solve(list);
List<String> out = new ArrayList<String>();
for (Rect rect : list)
if(!out.contains(rect.toString()))
out.add(rect.toString());
Collections.sort(out);
sb.append(out.size());
sb.append('\n');
for (int i = 0; i < out.size(); i++) {
sb.append(out.get(i));
if (i != out.size() - 1)
sb.append('\n');
}
System.out.print(sb);
}
public static List<Rect> solve(List<Rect> in) {
List<Rect> out = new ArrayList<Rect>();
int n = -1;
long rst = 0, dst = 0;
while (n != 0) {
List<Coord> xCoords = new ArrayList<Coord>();
root = null;
Map<Rect, List<Rect>> map = new TreeMap<Rect, List<Rect>>();
for (Rect rect : in) {
Coord coord = new Coord((int) rect.x, true);
coord.rect = rect;
xCoords.add(coord);
coord = new Coord((int) (rect.x + rect.width), false);
coord.rect = rect;
xCoords.add(coord);
}
Collections.sort(xCoords);
for (Coord coord : xCoords) {
if (coord.isLeft) {
long time = System.nanoTime();
List<Rect> res = rangeSearch(root, (int) coord.rect.y, (int) (coord.rect.y + coord.rect.height));
time = System.nanoTime() - time;
rst += time;
//System.out.println("RS " + time);
if(res !=null)
for (Rect rect :res
)
if (isFieldGTZero(coord.rect, rect)&&
!(rect.x == coord.rect.x && rect.y == coord.rect.y &&
rect.width == coord.rect.width && rect.height == coord.rect.height)) {
if (map.get(coord.rect) != null) {
map.get(coord.rect).add(rect);
int idx = Collections.binarySearch(in,rect);
if(idx>=0)
in.remove(idx);
} else {
List<Rect> l = new ArrayList<Rect>();
l.add(rect);
map.put(coord.rect, l);
int idx = Collections.binarySearch(in,rect);
if(idx>=0)
in.remove(idx);
idx = Collections.binarySearch(in,coord.rect);
if(idx>=0)
in.remove(idx);
}
}
AVLTreeNode node = new AVLTreeNode((int) coord.rect.y, coord.rect);
insertAVL(root,node);
node = new AVLTreeNode((int)(coord.rect.y + coord.rect.height), coord.rect);
insertAVL(root,node);
} else {
removeAVL(root, (int) coord.rect.y);
removeAVL(root, (int) (coord.rect.y + coord.rect.height));
}
}
n = map.size();
long time = System.nanoTime();
Map<Integer, List<Rect>> ds = getDisjointSets(map);
time = System.nanoTime() - time;
dst += time;
//System.out.println("DS " + time);
List<Rect> in2 = new ArrayList<Rect>();
int i = 0;
for (List<Rect> list : ds.values()) {
Rect r = enclose(list);
r.number = ++i;
in2.add(r);
}
for (int j=0;j<in.size();j++) {
Rect rect = in.get(j);
rect.number = ++i;
in2.add(rect);
}
in = in2;
if (n == 0)
out.addAll(in);
}
return out;
}
static Map<Integer, List<Rect>> getDisjointSets(Map<Rect, List<Rect>> in) {
Map<Integer, Integer> map = new TreeMap<Integer, Integer>();
Map<Integer, List<Rect>> res = new TreeMap<Integer, List<Rect>>();
for (Map.Entry<Rect, List<Rect>> entry : in.entrySet()) {
map.put((int) entry.getKey().number, (int) entry.getKey().number);
for (Rect rect : entry.getValue()) {
map.put((int) rect.number, (int) rect.number);
}
}
for (Map.Entry<Rect, List<Rect>> entry : in.entrySet()) {
if (!res.containsKey(map.get((int)entry.getKey().number))) {
List<Rect> l = new ArrayList<Rect>();
l.add(entry.getKey());
res.put((int) map.get((int) entry.getKey().number), l);
}
for (Rect rect : entry.getValue()) {
if (map.get((int) entry.getKey().number) != map.get((int) rect.number)) {
map.put((int) rect.number, (int) map.get((int) entry.getKey().number));
res.get((int) map.get((int) entry.getKey().number)).add(rect);
}
}
}
return res;
}
static class Coord implements Comparable<Coord> {
int c;
boolean isLeft = false;
Rect rect;
public Coord(int c, boolean isLeft) {
this.c = c;
this.isLeft = isLeft;
}
@Override
public int compareTo(Coord o) {
return c > o.c ? 1 : c == o.c ? 0 : -1;
}
}
static Rect enclose(List<Rect> list) {
long topLeftX = Integer.MAX_VALUE;
long topLeftY = Integer.MAX_VALUE;
long bottomRightX = Integer.MIN_VALUE;
long bottomRightY = Integer.MIN_VALUE;
for (Rect r : list) {
if (r.x < topLeftX)
topLeftX = r.x;
if (r.y < topLeftY)
topLeftY = r.y;
if ((r.x + r.width) > bottomRightX)
bottomRightX = (r.x + r.width);
if ((r.y + r.height) > bottomRightY)
bottomRightY = (r.y + r.height);
}
Rect res = new Rect();
res.x = topLeftX;
res.y = topLeftY;
res.width = bottomRightX - topLeftX;
res.height = bottomRightY - topLeftY;
return res;
}
static class Rect implements Comparable<Rect> {
long x, y, width, height, number;
@Override
public int compareTo(Rect o) {
return (int)(number - o.number); //To change body of implemented methods use File | Settings | File Templates.
}
@Override
public int hashCode() {
return (int)number;
}
@Override
public boolean equals(Object obj) {
if (!(obj instanceof Rect))
return false;
return number == ((Rect) obj).number; //To change body of overridden methods use File | Settings | File Templates.
}
@Override
public String toString() {
return x + " " + (x + width) + " " + y + " " + (y + height); //To change body of overridden methods use File | Settings | File Templates.
}
}
public static List<Rect> rangeSearch(AVLTreeNode node, int k1, int k2) {
if(node == null ){
if(root == null)
return new ArrayList<Rect>();
return null;
}
if(node.value>=k1 && node.value <= k2){
List<Rect> l = rangeSearch(node.left,k1,k2);
List<Rect> r = rangeSearch(node.right,k1,k2);
if(l == null)
l = new ArrayList<Rect>();
Collections.sort(l);
if(r!=null)
for(Rect rect : r) {
int idx= Collections.binarySearch(l,rect);
if(idx<0)
l.add((~idx),rect);
}
int idx = Collections.binarySearch(l,node.val);
if(idx<0)
l.add((~idx),node.val);
return l;
} else if(node.value<k1){
List<Rect> r = rangeSearch(node.right,k1,k2);
if(node.val.y<=k1 && node.val.y + node.val.height>=k2){
if(r == null){
List<Rect> res = new ArrayList<Rect>();
res.add(node.val);
r = res;
}
else {
int idx = Collections.binarySearch(r,node.val);
if(idx<0)
r.add(~(idx),node.val);
}
}
return r;
} else if(node.value>k2)
{
List<Rect> l = rangeSearch(node.left, k1,k2);
if(node.val.y<=k1 && node.val.y + node.val.height>=k2){
if(l == null){
List<Rect> res = new ArrayList<Rect>();
res.add(node.val);
l = res;
}
else {
int idx = Collections.binarySearch(l,node.val);
if(idx<0)
l.add(~idx,node.val);
}
}
return l;
}
return null;
}
public static boolean isFieldGTZero(Rect r1, Rect r2) {
if ((r1.x + r1.width == r2.x) || r2.x + r2.width == r1.x ||
r1.y + r1.height == r2.y || r2.y + r2.height == r1.y
)
return false;
return true;
}
static class AVLTreeNode
{
int value;
AVLTreeNode left;
AVLTreeNode right;
AVLTreeNode parent;
int balance;
Rect val;
AVLTreeNode (int val, Rect rect)
{
value = val;
balance = 0;
this.val = rect;
}
}
private static void setBalance(AVLTreeNode cur) {
cur.balance = height(cur.right)-height(cur.left);
}
public static void insertAVL(AVLTreeNode p, AVLTreeNode q) {
if(p==null) {
root=q;
} else {
if(q.value<p.value) {
if(p.left==null) {
p.left = q;
q.parent = p;
recursiveBalance(p);
} else {
insertAVL(p.left,q);
}
} else if(q.value>p.value) {
if(p.right==null) {
p.right = q;
q.parent = p;
recursiveBalance(p);
} else {
insertAVL(p.right,q);
}
} else {
}
}
}
public static void recursiveBalance(AVLTreeNode cur) {
setBalance(cur);
int balance = cur.balance;
if(balance==-2) {
if(height(cur.left.left)>=height(cur.left.right)) {
cur = rotateRight(cur);
} else {
cur = doubleRotateLeftRight(cur);
}
} else if(balance==2) {
if(height(cur.right.right)>=height(cur.right.left)) {
cur = rotateLeft(cur);
} else {
cur = doubleRotateRightLeft(cur);
}
}
// we did not reach the root yet
if(cur.parent!=null) {
recursiveBalance(cur.parent);
} else {
root = cur;
}
}
public static void removeAVL(AVLTreeNode p,int q) {
if(p==null) {
// der Wert existiert nicht in diesem Baum, daher ist nichts zu tun
return;
} else {
if(p.value>q) {
removeAVL(p.left,q);
} else if(p.value<q) {
removeAVL(p.right,q);
} else if(p.value==q) {
// we found the node in the tree.. now lets go on!
removeFoundNode(p);
}
}
}
public static void removeFoundNode(AVLTreeNode q) {
AVLTreeNode r;
// at least one child of q, q will be removed directly
if(q.left==null || q.right==null) {
// the root is deleted
if(q.parent==null) {
root=null;
q=null;
return;
}
r = q;
} else {
// q has two children --> will be replaced by successor
r = successor(q);
q.value = r.value;
}
AVLTreeNode p;
if(r.left!=null) {
p = r.left;
} else {
p = r.right;
}
if(p!=null) {
p.parent = r.parent;
}
if(r.parent==null) {
root = p;
} else {
if(r==r.parent.left) {
r.parent.left=p;
} else {
r.parent.right = p;
}
// balancing must be done until the root is reached.
recursiveBalance(r.parent);
}
r = null;
}
public static AVLTreeNode rotateLeft(AVLTreeNode n) {
AVLTreeNode v = n.right;
v.parent = n.parent;
n.right = v.left;
if(n.right!=null) {
n.right.parent=n;
}
v.left = n;
n.parent = v;
if(v.parent!=null) {
if(v.parent.right==n) {
v.parent.right = v;
} else if(v.parent.left==n) {
v.parent.left = v;
}
}
setBalance(n);
setBalance(v);
return v;
}
public static AVLTreeNode rotateRight(AVLTreeNode n) {
AVLTreeNode v = n.left;
v.parent = n.parent;
n.left = v.right;
if(n.left!=null) {
n.left.parent=n;
}
v.right = n;
n.parent = v;
if(v.parent!=null) {
if(v.parent.right==n) {
v.parent.right = v;
} else if(v.parent.left==n) {
v.parent.left = v;
}
}
setBalance(n);
setBalance(v);
return v;
}
public static AVLTreeNode doubleRotateLeftRight(AVLTreeNode u) {
u.left = rotateLeft(u.left);
return rotateRight(u);
}
public static AVLTreeNode doubleRotateRightLeft(AVLTreeNode u) {
u.right = rotateRight(u.right);
return rotateLeft(u);
}
/***************************** Helper Functions ************************************/
public static AVLTreeNode successor(AVLTreeNode q) {
if(q.right!=null) {
AVLTreeNode r = q.right;
while(r.left!=null) {
r = r.left;
}
return r;
} else {
AVLTreeNode p = q.parent;
while(p!=null && q==p.right) {
q = p;
p = q.parent;
}
return p;
}
}
private static int height(AVLTreeNode cur) {
if(cur==null) {
return -1;
}
if(cur.left==null && cur.right==null) {
return 0;
} else if(cur.left==null) {
return 1+height(cur.right);
} else if(cur.right==null) {
return 1+height(cur.left);
} else {
return 1+maximum(height(cur.left),height(cur.right));
}
}
private static int maximum(int a, int b) {
if(a>=b) {
return a;
} else {
return b;
}
}
}
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import java.io.InputStreamReader; import java.util.*; public class ple { static AVLTreeNode root = null; public static void main(String[] args) throws Exception { BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); String line; StringBuilder sb = new StringBuilder(); int n; line = br.readLine(); n = Integer.parseInt(line); List<Rect> list = new ArrayList<Rect>(); for (int i = 0; i < n; i++) { line = br.readLine(); String[] tab = line.split(" "); Rect rect = new Rect(); rect.x = Long.parseLong(tab[0]); rect.width = Long.parseLong(tab[1]) - rect.x; rect.y = Long.parseLong(tab[2]); rect.height = Long.parseLong(tab[3]) - rect.y; rect.number = i + 1; list.add(rect); } list = solve(list); List<String> out = new ArrayList<String>(); for (Rect rect : list) if(!out.contains(rect.toString())) out.add(rect.toString()); Collections.sort(out); sb.append(out.size()); sb.append('\n'); for (int i = 0; i < out.size(); i++) { sb.append(out.get(i)); if (i != out.size() - 1) sb.append('\n'); } System.out.print(sb); } public static List<Rect> solve(List<Rect> in) { List<Rect> out = new ArrayList<Rect>(); int n = -1; long rst = 0, dst = 0; while (n != 0) { List<Coord> xCoords = new ArrayList<Coord>(); root = null; Map<Rect, List<Rect>> map = new TreeMap<Rect, List<Rect>>(); for (Rect rect : in) { Coord coord = new Coord((int) rect.x, true); coord.rect = rect; xCoords.add(coord); coord = new Coord((int) (rect.x + rect.width), false); coord.rect = rect; xCoords.add(coord); } Collections.sort(xCoords); for (Coord coord : xCoords) { if (coord.isLeft) { long time = System.nanoTime(); List<Rect> res = rangeSearch(root, (int) coord.rect.y, (int) (coord.rect.y + coord.rect.height)); time = System.nanoTime() - time; rst += time; //System.out.println("RS " + time); if(res !=null) for (Rect rect :res ) if (isFieldGTZero(coord.rect, rect)&& !(rect.x == coord.rect.x && rect.y == coord.rect.y && rect.width == coord.rect.width && rect.height == coord.rect.height)) { if (map.get(coord.rect) != null) { map.get(coord.rect).add(rect); int idx = Collections.binarySearch(in,rect); if(idx>=0) in.remove(idx); } else { List<Rect> l = new ArrayList<Rect>(); l.add(rect); map.put(coord.rect, l); int idx = Collections.binarySearch(in,rect); if(idx>=0) in.remove(idx); idx = Collections.binarySearch(in,coord.rect); if(idx>=0) in.remove(idx); } } AVLTreeNode node = new AVLTreeNode((int) coord.rect.y, coord.rect); insertAVL(root,node); node = new AVLTreeNode((int)(coord.rect.y + coord.rect.height), coord.rect); insertAVL(root,node); } else { removeAVL(root, (int) coord.rect.y); removeAVL(root, (int) (coord.rect.y + coord.rect.height)); } } n = map.size(); long time = System.nanoTime(); Map<Integer, List<Rect>> ds = getDisjointSets(map); time = System.nanoTime() - time; dst += time; //System.out.println("DS " + time); List<Rect> in2 = new ArrayList<Rect>(); int i = 0; for (List<Rect> list : ds.values()) { Rect r = enclose(list); r.number = ++i; in2.add(r); } for (int j=0;j<in.size();j++) { Rect rect = in.get(j); rect.number = ++i; in2.add(rect); } in = in2; if (n == 0) out.addAll(in); } return out; } static Map<Integer, List<Rect>> getDisjointSets(Map<Rect, List<Rect>> in) { Map<Integer, Integer> map = new TreeMap<Integer, Integer>(); Map<Integer, List<Rect>> res = new TreeMap<Integer, List<Rect>>(); for (Map.Entry<Rect, List<Rect>> entry : in.entrySet()) { map.put((int) entry.getKey().number, (int) entry.getKey().number); for (Rect rect : entry.getValue()) { map.put((int) rect.number, (int) rect.number); } } for (Map.Entry<Rect, List<Rect>> entry : in.entrySet()) { if (!res.containsKey(map.get((int)entry.getKey().number))) { List<Rect> l = new ArrayList<Rect>(); l.add(entry.getKey()); res.put((int) map.get((int) entry.getKey().number), l); } for (Rect rect : entry.getValue()) { if (map.get((int) entry.getKey().number) != map.get((int) rect.number)) { map.put((int) rect.number, (int) map.get((int) entry.getKey().number)); res.get((int) map.get((int) entry.getKey().number)).add(rect); } } } return res; } static class Coord implements Comparable<Coord> { int c; boolean isLeft = false; Rect rect; public Coord(int c, boolean isLeft) { this.c = c; this.isLeft = isLeft; } @Override public int compareTo(Coord o) { return c > o.c ? 1 : c == o.c ? 0 : -1; } } static Rect enclose(List<Rect> list) { long topLeftX = Integer.MAX_VALUE; long topLeftY = Integer.MAX_VALUE; long bottomRightX = Integer.MIN_VALUE; long bottomRightY = Integer.MIN_VALUE; for (Rect r : list) { if (r.x < topLeftX) topLeftX = r.x; if (r.y < topLeftY) topLeftY = r.y; if ((r.x + r.width) > bottomRightX) bottomRightX = (r.x + r.width); if ((r.y + r.height) > bottomRightY) bottomRightY = (r.y + r.height); } Rect res = new Rect(); res.x = topLeftX; res.y = topLeftY; res.width = bottomRightX - topLeftX; res.height = bottomRightY - topLeftY; return res; } static class Rect implements Comparable<Rect> { long x, y, width, height, number; @Override public int compareTo(Rect o) { return (int)(number - o.number); //To change body of implemented methods use File | Settings | File Templates. } @Override public int hashCode() { return (int)number; } @Override public boolean equals(Object obj) { if (!(obj instanceof Rect)) return false; return number == ((Rect) obj).number; //To change body of overridden methods use File | Settings | File Templates. } @Override public String toString() { return x + " " + (x + width) + " " + y + " " + (y + height); //To change body of overridden methods use File | Settings | File Templates. } } public static List<Rect> rangeSearch(AVLTreeNode node, int k1, int k2) { if(node == null ){ if(root == null) return new ArrayList<Rect>(); return null; } if(node.value>=k1 && node.value <= k2){ List<Rect> l = rangeSearch(node.left,k1,k2); List<Rect> r = rangeSearch(node.right,k1,k2); if(l == null) l = new ArrayList<Rect>(); Collections.sort(l); if(r!=null) for(Rect rect : r) { int idx= Collections.binarySearch(l,rect); if(idx<0) l.add((~idx),rect); } int idx = Collections.binarySearch(l,node.val); if(idx<0) l.add((~idx),node.val); return l; } else if(node.value<k1){ List<Rect> r = rangeSearch(node.right,k1,k2); if(node.val.y<=k1 && node.val.y + node.val.height>=k2){ if(r == null){ List<Rect> res = new ArrayList<Rect>(); res.add(node.val); r = res; } else { int idx = Collections.binarySearch(r,node.val); if(idx<0) r.add(~(idx),node.val); } } return r; } else if(node.value>k2) { List<Rect> l = rangeSearch(node.left, k1,k2); if(node.val.y<=k1 && node.val.y + node.val.height>=k2){ if(l == null){ List<Rect> res = new ArrayList<Rect>(); res.add(node.val); l = res; } else { int idx = Collections.binarySearch(l,node.val); if(idx<0) l.add(~idx,node.val); } } return l; } return null; } public static boolean isFieldGTZero(Rect r1, Rect r2) { if ((r1.x + r1.width == r2.x) || r2.x + r2.width == r1.x || r1.y + r1.height == r2.y || r2.y + r2.height == r1.y ) return false; return true; } static class AVLTreeNode { int value; AVLTreeNode left; AVLTreeNode right; AVLTreeNode parent; int balance; Rect val; AVLTreeNode (int val, Rect rect) { value = val; balance = 0; this.val = rect; } } private static void setBalance(AVLTreeNode cur) { cur.balance = height(cur.right)-height(cur.left); } public static void insertAVL(AVLTreeNode p, AVLTreeNode q) { if(p==null) { root=q; } else { if(q.value<p.value) { if(p.left==null) { p.left = q; q.parent = p; recursiveBalance(p); } else { insertAVL(p.left,q); } } else if(q.value>p.value) { if(p.right==null) { p.right = q; q.parent = p; recursiveBalance(p); } else { insertAVL(p.right,q); } } else { } } } public static void recursiveBalance(AVLTreeNode cur) { setBalance(cur); int balance = cur.balance; if(balance==-2) { if(height(cur.left.left)>=height(cur.left.right)) { cur = rotateRight(cur); } else { cur = doubleRotateLeftRight(cur); } } else if(balance==2) { if(height(cur.right.right)>=height(cur.right.left)) { cur = rotateLeft(cur); } else { cur = doubleRotateRightLeft(cur); } } // we did not reach the root yet if(cur.parent!=null) { recursiveBalance(cur.parent); } else { root = cur; } } public static void removeAVL(AVLTreeNode p,int q) { if(p==null) { // der Wert existiert nicht in diesem Baum, daher ist nichts zu tun return; } else { if(p.value>q) { removeAVL(p.left,q); } else if(p.value<q) { removeAVL(p.right,q); } else if(p.value==q) { // we found the node in the tree.. now lets go on! removeFoundNode(p); } } } public static void removeFoundNode(AVLTreeNode q) { AVLTreeNode r; // at least one child of q, q will be removed directly if(q.left==null || q.right==null) { // the root is deleted if(q.parent==null) { root=null; q=null; return; } r = q; } else { // q has two children --> will be replaced by successor r = successor(q); q.value = r.value; } AVLTreeNode p; if(r.left!=null) { p = r.left; } else { p = r.right; } if(p!=null) { p.parent = r.parent; } if(r.parent==null) { root = p; } else { if(r==r.parent.left) { r.parent.left=p; } else { r.parent.right = p; } // balancing must be done until the root is reached. recursiveBalance(r.parent); } r = null; } public static AVLTreeNode rotateLeft(AVLTreeNode n) { AVLTreeNode v = n.right; v.parent = n.parent; n.right = v.left; if(n.right!=null) { n.right.parent=n; } v.left = n; n.parent = v; if(v.parent!=null) { if(v.parent.right==n) { v.parent.right = v; } else if(v.parent.left==n) { v.parent.left = v; } } setBalance(n); setBalance(v); return v; } public static AVLTreeNode rotateRight(AVLTreeNode n) { AVLTreeNode v = n.left; v.parent = n.parent; n.left = v.right; if(n.left!=null) { n.left.parent=n; } v.right = n; n.parent = v; if(v.parent!=null) { if(v.parent.right==n) { v.parent.right = v; } else if(v.parent.left==n) { v.parent.left = v; } } setBalance(n); setBalance(v); return v; } public static AVLTreeNode doubleRotateLeftRight(AVLTreeNode u) { u.left = rotateLeft(u.left); return rotateRight(u); } public static AVLTreeNode doubleRotateRightLeft(AVLTreeNode u) { u.right = rotateRight(u.right); return rotateLeft(u); } /***************************** Helper Functions ************************************/ public static AVLTreeNode successor(AVLTreeNode q) { if(q.right!=null) { AVLTreeNode r = q.right; while(r.left!=null) { r = r.left; } return r; } else { AVLTreeNode p = q.parent; while(p!=null && q==p.right) { q = p; p = q.parent; } return p; } } private static int height(AVLTreeNode cur) { if(cur==null) { return -1; } if(cur.left==null && cur.right==null) { return 0; } else if(cur.left==null) { return 1+height(cur.right); } else if(cur.right==null) { return 1+height(cur.left); } else { return 1+maximum(height(cur.left),height(cur.right)); } } private static int maximum(int a, int b) { if(a>=b) { return a; } else { return b; } } } |