带插入排序的java排序字符串数组标记,双链表
我正在做一项任务,我必须对数组进行排序,并将索引存储在我构建的双链表ADT中
Example:
{"A","B","C","A"} -> {0,3,1,2}
我当前的方法是将索引引入ADT,然后在对数组排序时对ADT进行排序。据我所知,每次执行任何一个循环时,我都对数组和双链表执行完全相同的操作,但我的输出不匹配
public static void main(String[] args ) {
List A = new List();
String[] inputArray = {"A","C","B","A"};
int i,j;
String key;
//load indices into doubly-linked list
for (int x = 0; x < inputArray.length; x++ ) {
A.append(x);
}
//begin insertion sort
for (j = 1; j < inputArray.length; j++) {
System.out.println(A);
System.out.println(Arrays.toString(inputArray));
key = inputArray[j];
i = j - 1;
while (i >= 0) {
if (key.compareTo(inputArray[i]) > 0) {
break;
}
inputArray[i+1] = inputArray[i];
//moveTo moves the cursor to <int>
A.moveTo(i);
//make sure we aren't trying to insert before first node
if (i > 0) { A.insertBefore(i+1); }
else { A.prepend(i+1); }
//remove node at cursor
A.delete();
i--;
}
inputArray[i+1] = key;
A.moveTo(i+1);
if (i > 0) { A.insertBefore(i+1); }
else { A.prepend(i+1); }
A.delete();
}
System.out.println(A);
System.out.println(Arrays.toString(inputArray));
}
上述代码给出以下输出:
运行:
01 2 3
[A,C,B,A]
1023
[A,C,B,A]
1 12 3
[A,B,C,A]
0233
[A,A,B,C]
生成成功(总时间:0秒)
编辑:列表。爪哇
public class List {
private class Node{
//Fields
int data;
Node next, previous;
//Constructor
Node(int data) {
this.data = data;
next = null;
previous = null;
}
public String toString() { return String.valueOf(data); }
}
//Fields
private Node frontNode, backNode, cursorNode;
private int totalSize, cursorPosition;
//Constructor
List() {
frontNode = backNode = cursorNode = null;
totalSize = 0;
cursorPosition = -1;
}
//moveTo(int i): If 0<=i<=length()-1, moves the cursor to the element
// at index i, otherwise the cursor becomes undefined.
void moveTo(int i) {
if (i == 0) {
cursorPosition = i;
cursorNode = frontNode;
}
else if (i == length() - 1) {
cursorPosition = i;
cursorNode = backNode;
}
else if (i > 0 && i < length() - 1 ) {
cursorNode = frontNode;
cursorPosition = i;
for (int x=0; x < i; x++) {
cursorNode = cursorNode.next;
}
}
else {
cursorPosition = -1;
}
}
//prepend(int data): Inserts new element before front element in this List.
void prepend(int data) {
Node node = new Node(data);
if ( this.length() == 0 ) {
frontNode = backNode = node;
}
else {
frontNode.previous = node;
node.next = frontNode;
frontNode = node;
}
totalSize++;
//cursorPosition might change?
}
//insertBefore(int data): Inserts new element before cursor element in this
// List. Pre: length()>0, getIndex()>=0
void insertBefore(int data) {
Node node = new Node(data);
if ( this.length() > 0 && this.getIndex() >= 0 ) {
node.previous = cursorNode.previous;
node.next = cursorNode;
cursorNode.previous.next = node;
cursorNode.previous = node;
totalSize++;
}
else if ( this.length() <= 0 )
{
throw new RuntimeException
("Error: insertBefore called on empty list");
}
else {
throw new RuntimeException
("Error: insertBefore called without cursor set");
}
}
# 1 楼答案
好的,谢谢。我不知道insertBefore()和prepend()到底要做什么(我本可以猜到,但编程不应该是猜测方法应该做什么;查看文档要好得多)
既然这是一项作业,我就不给你答案了。但线索是这样的:在第一次通过循环之后,A的转储将提供与开始时相同的索引,但会重新排列。我认为这就是每次循环迭代后应该采用的方式。但在第二次通过循环后,情况并非如此(1出现两次,0消失)。想想看。当您调用A.insertBefore()来重新排列A的元素时,您应该告诉insertBefore()插入哪些数据,您实际插入了什么