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我們的教師告訴我們添加一個max方法來返回列表中最大的元素並寫入方法max的定義,問題是因爲它已經有一個maxListSize,它返回列表的最大尺寸是否需要再次使用aa max方法?添加max方法返回列表中的最大元素
public abstract class ArrayListClass {
protected int length;
protected int maxSize;
protected DataElement[] list;
public ArrayListClass(){
length = 0;
maxSize = 100;
list = new DataElement[maxSize];
}
public ArrayListClass(int size){
if(size < 0){
System.out.println("The array size must be positive. Creating an array of size 100...");
}else{
maxSize = size;
}
length = 0;
list = new DataElement[maxSize];
}
//copy constructor
public ArrayListClass(ArrayListClass otherList){
maxSize = otherList.maxSize;
length = otherList.length;
list = new DataElement[maxSize];
for(int j = 0; j < length; j++){
list[j] = otherList.list[j].getCopy();
}
}
public boolean isEmpty(){
return (length == 0);
}
public boolean isFull(){
return (length == maxSize);
}
/*
* method that returns the number of elements
* in the list
*/
public int listSize(){
return length;
}
/*
* method that returns the maximum size
* of the list
*/
public int maxListSize(){
return maxSize;
}
/*
* method that prints the elements of the list
*/
public void print(){
for(int index = 0; index < length; index++){
System.out.print(list[index].getCopy() + " ");
}
System.out.println();
}
/*
* method that determines whether an item is the
* same as the item in the list at the position
* specified by location
*/
public boolean isItemAtEqual(int location, DataElement item){
return (list[location].equals(item));
}
/*
* method that inserts insertItem in the list
* at the position specified by location
*/
public void insertAt(int location, DataElement insertItem){
if(location < 0 || location >= maxSize){
System.out.println("The position of the item to be inserted is out of range.");
}else{
if(length >= maxSize){
System.out.println("Cannot insert in a full list");
}else{
for(int index = length; index > location; index--){
list[index] = list[index-1];
}
list[location] = insertItem.getCopy();
length++;
}
}
}
public void insertEnd(DataElement insertItem){
if(length >= maxSize){
System.out.println("Cannot insert in a full list");
}else{
list[length] = insertItem.getCopy();
length++;
}
}
public void removeAt(int location){
if(location < 0 || location >= length){
System.out.println("The location of the item to be removed is out of range.");
}else{
for(int index = location; index < length; index++){
list[index] = list[index + 1];
}
list[length-1] = null;
length--;
}
}
/*
* method that retrieves the element from the list
* at the position specified by location
*/
public DataElement retrieveAt(int location){
if(location < 0 || location >= length){
System.out.println("The location of the item to be retrieved is out of range.");
return null;
}else{
return list[location].getCopy();
}
}
public void replaceAt(int location, DataElement repItem){
if(location < 0 || location >= length){
System.out.println("The location of the item to be replaced is out of range.");
}else{
list[location].makeCopy(repItem);
}
}
public void clearList(){
for(int index = 0; index < length; index++){
list[index] = null;
}
length = 0;
}
public void copyList(ArrayListClass otherList){
if(this != otherList){
for(int index = 0; index < length; index++){
list[index] = null;
}
maxSize = otherList.maxSize;
length = otherList.length;
list = new DataElement[maxSize];
for(int index = 0; index < length; index++){
list[index] = otherList.list[index].getCopy();
}
}
}
public abstract int seqSearch(DataElement searchItem);
public abstract void insert(DataElement insertItem);
public abstract void remove(DataElement removeItem);
public abstract void removeAll (DataElement removeAllItem);
}
我不明白這個問題。你能詳細說明嗎? – nicomp
SO不適合你完成作業。我可以告訴你,這個方法很容易寫。你只需要通過元素,並保留另一個變量,它可以保存最大值。當您完成迭代列表時,您將擁有最大尺寸的元素。還有什麼'問題是因爲它已經有一個maxListSize來返回列表的最大尺寸.'意思是? –
@nicomp我是否需要添加另一個最大方法?既然已經有一個方法返回最大尺寸 –