Java 将等价图合并在一起
我不明白如何使两个图形合并在一起。见下图: 这里我想合并两个图,根是A和E。由于E较小,我想让它指向较大的图A的根。我有一个名为Java 将等价图合并在一起,java,algorithm,data-structures,hash,graph,Java,Algorithm,Data Structures,Hash,Graph,我不明白如何使两个图形合并在一起。见下图: 这里我想合并两个图,根是A和E。由于E较小,我想让它指向较大的图A的根。我有一个名为compressoroot()的函数,它接受一个参数,使其自身和根之间的每个节点指向自参考根(例如,compressoroot(D)):D->A,C->A,B->A)。如果我有这个功能 public Equivalence<E> mergeClassesContaining(E a, E b); 如何完成mergeClassesContaining(ea
compressoroot()
的函数,它接受一个参数,使其自身和根之间的每个节点指向自参考根(例如,compressoroot(D)):D->A,C->A,B->A)。如果我有这个功能
public Equivalence<E> mergeClassesContaining(E a, E b);
如何完成mergeClassesContaining(ea,eb)
函数,以便它确定哪个是较小的图形,并将其根指向较大的图形?在这种情况下,图形根据其“节点”的数量而变大或变小。例如,左侧有4个,右侧有2个
public Equivalence<E> mergeClassesContaining(E a, E b) throws IllegalArgumentException {
if (!inSameClass(a, b)) { //private function to determine if the given parameters are in the same class.
//need help here.
return this;
}
}
公共等价合并类包含(EA,EB)抛出IllegalArgumentException{
if(!inSameClass(a,b)){//private函数来确定给定参数是否在同一个类中。
//这里需要帮助。
归还这个;
}
}
以下是CompressorRoot函数:
private E compressToRoot (E e) throws IllegalArgumentException {
E node;
ArrayList<E> nodes = new ArrayList<E>();
while ((node = parentMap.get(e)) != e) {
nodes.add(e);
e = node;
}
for (E element : nodes)
((ArrayList<E>) parentMap).set((Integer) node, e);
return e;
}
private E compressoroot(E)抛出IllegalArgumentException{
E节点;
ArrayList节点=新的ArrayList();
while((node=parentMap.get(e))!=e){
节点。添加(e);
e=节点;
}
对于(E元素:节点)
((ArrayList)parentMap.set((Integer)节点,e);
返回e;
}
完整代码:
public class HashEquivalence<E> implements Equivalence<E> {
public Equivalence<E> addSingletonClass (E e) throws IllegalArgumentException {
if (parentMap.containsKey(e))
throw new IllegalArgumentException("HashEquivalence.addSingletonClass: e(" +e+ ") already in an equivalence class");
parentMap.put(e,e); //its own parent
rootSizeMap.put(e,1); //its equivalence class has 1 value in it
return this;
}
private E compressToRoot (E e) throws IllegalArgumentException {
E node;
ArrayList<E> nodes = new ArrayList<E>();
while ((node = parentMap.get(e)) != e) {
nodes.add(e);
e = node;
}
for (E element : nodes)
((ArrayList<E>) parentMap).set((Integer) node, e);
return e; //Allows method to compile
}
public boolean inSameClass(E a, E b) throws IllegalArgumentException {
if (!parentMap.containsKey(a))
throw new IllegalArgumentException("HashEquivalence.inSameClass: a(" +a+ ") not in an equivalence class");
if (!parentMap.containsKey(b))
throw new IllegalArgumentException("HashEquivalence.inSameClass: b(" +b+ ") not in an equivalence class");
return compressToRoot(a) == compressToRoot(b);
}
public Equivalence<E> mergeClassesContaining(E a, E b) throws IllegalArgumentException {
if (!inSameClass(a,b))
return this;
}
public Set<Set<E>> allClasses () {
Map<E,Set<E>> answerMap = new HashMap<E,Set<E>>();
for (E e : parentMap.keys()) {
E root = compressToRoot(e);
Set<E> s = answerMap.get(root);
if (s == null)
answerMap.put(root, s = new HashSet<E>());
s.add(e);
}
return new HashSet<Set<E>>(1.0,answerMap.values());
}
public int numberOfClasses ()
{return rootSizeMap.size();}
public int numberOfMembers ()
{return parentMap.size();}
private Map<E,Integer> heights () {
Map<E,Integer> answer = new HashMap<E,Integer>();
for (E element : parentMap.keys()) {
E e = element;
int depth = 0;
while (parentMap.get(e) != e) {
e = parentMap.get(e);
depth++;
}
Integer soFar = answer.get(e);
if (soFar == null || soFar < depth)
answer.put(e, depth);
}
return answer;
}
public int maxHeight () {
return Collections.max(heights().values());
}
public void showMaps() {
System.out.println("parentMap (as list) = " + new ArrayList<Map.Entry<E,E>>(parentMap.entries()));
System.out.println("rootSizeMap (as list) = " + new ArrayList<Map.Entry<E,Integer>>(rootSizeMap.entries()));
System.out.println("heightMap (as list) = " + new ArrayList<Map.Entry<E,Integer>>(heights().entries()));
System.out.println("max height of tree = " + maxHeight());
}
private Map<E,E> parentMap = new HashMap<E,E>();
private Map<E,Integer> rootSizeMap = new HashMap<E,Integer>();
}
公共类hashequality实现了等价性{
公共等价addSingletonClass(E)抛出IllegalArgumentException{
if(parentMap.containsKey(e))
抛出新的IllegalArgumentException(“HashEquivalence.addSingletonClass:e(“+e+”)已在等价类中”);
parentMap.put(e,e);//它自己的父对象
rootSizeMap.put(e,1);//其等价类中有1个值
归还这个;
}
private E CompressorRoot(E E)抛出IllegalArgumentException{
E节点;
ArrayList节点=新的ArrayList();
while((node=parentMap.get(e))!=e){
节点。添加(e);
e=节点;
}
对于(E元素:节点)
((ArrayList)parentMap.set((Integer)节点,e);
返回e;//允许方法编译
}
公共布尔inSameClass(ea,eb)抛出IllegalArgumentException{
如果(!parentMap.containsKey(a))
抛出新的IllegalArgumentException(“HashEquivalence.inSameClass:a(“+a+”)不在等价类中”);
如果(!parentMap.containsKey(b))
抛出新的IllegalArgumentException(“HashEquivalence.inSameClass:b(“+b+”)不在等价类中”);
返回压缩机启动(a)=压缩机启动(b);
}
公共等价合并类包含(EA,EB)抛出IllegalArgumentException{
如果(!inSameClass(a,b))
归还这个;
}
公共集合所有类(){
Map answerMap=新HashMap();
对于(E:parentMap.keys()){
E根=压缩机根(E);
Set s=answerMap.get(根);
如果(s==null)
put(root,s=newhashset());
s、 加(e);
}
返回新的HashSet(1.0,answerMap.values());
}
公共int numberOfClasses()
{返回rootSizeMap.size();}
公共int numberOfMembers()
{返回parentMap.size();}
私人地图高度(){
Map answer=new HashMap();
对于(E元素:parentMap.keys()){
E=元素;
int深度=0;
while(parentMap.get(e)!=e){
e=parentMap.get(e);
深度++;
}
整数soFar=answer.get(e);
if(soFar==null | | soFar
什么是“小班”?你在问题中遗漏了很多假设和背景。如果没有这些丢失的信息,它几乎是没有意义的。所以…第二步中的是一个不相交的图。你能解释一下这两个不相交的图是如何相互关联的吗?@user1766888诸如此类,你的实现是如此困难和错误……嗯,这是我在聊天中说的:所以,paste.org.ru/?2j783h
public class HashEquivalence<E> implements Equivalence<E> {
public Equivalence<E> addSingletonClass (E e) throws IllegalArgumentException {
if (parentMap.containsKey(e))
throw new IllegalArgumentException("HashEquivalence.addSingletonClass: e(" +e+ ") already in an equivalence class");
parentMap.put(e,e); //its own parent
rootSizeMap.put(e,1); //its equivalence class has 1 value in it
return this;
}
private E compressToRoot (E e) throws IllegalArgumentException {
E node;
ArrayList<E> nodes = new ArrayList<E>();
while ((node = parentMap.get(e)) != e) {
nodes.add(e);
e = node;
}
for (E element : nodes)
((ArrayList<E>) parentMap).set((Integer) node, e);
return e; //Allows method to compile
}
public boolean inSameClass(E a, E b) throws IllegalArgumentException {
if (!parentMap.containsKey(a))
throw new IllegalArgumentException("HashEquivalence.inSameClass: a(" +a+ ") not in an equivalence class");
if (!parentMap.containsKey(b))
throw new IllegalArgumentException("HashEquivalence.inSameClass: b(" +b+ ") not in an equivalence class");
return compressToRoot(a) == compressToRoot(b);
}
public Equivalence<E> mergeClassesContaining(E a, E b) throws IllegalArgumentException {
if (!inSameClass(a,b))
return this;
}
public Set<Set<E>> allClasses () {
Map<E,Set<E>> answerMap = new HashMap<E,Set<E>>();
for (E e : parentMap.keys()) {
E root = compressToRoot(e);
Set<E> s = answerMap.get(root);
if (s == null)
answerMap.put(root, s = new HashSet<E>());
s.add(e);
}
return new HashSet<Set<E>>(1.0,answerMap.values());
}
public int numberOfClasses ()
{return rootSizeMap.size();}
public int numberOfMembers ()
{return parentMap.size();}
private Map<E,Integer> heights () {
Map<E,Integer> answer = new HashMap<E,Integer>();
for (E element : parentMap.keys()) {
E e = element;
int depth = 0;
while (parentMap.get(e) != e) {
e = parentMap.get(e);
depth++;
}
Integer soFar = answer.get(e);
if (soFar == null || soFar < depth)
answer.put(e, depth);
}
return answer;
}
public int maxHeight () {
return Collections.max(heights().values());
}
public void showMaps() {
System.out.println("parentMap (as list) = " + new ArrayList<Map.Entry<E,E>>(parentMap.entries()));
System.out.println("rootSizeMap (as list) = " + new ArrayList<Map.Entry<E,Integer>>(rootSizeMap.entries()));
System.out.println("heightMap (as list) = " + new ArrayList<Map.Entry<E,Integer>>(heights().entries()));
System.out.println("max height of tree = " + maxHeight());
}
private Map<E,E> parentMap = new HashMap<E,E>();
private Map<E,Integer> rootSizeMap = new HashMap<E,Integer>();
}