堆排序的不正确实现



这是一个修改后的堆排序实现,取自一个网站。

import java.io.File;
import java.io.FileNotFoundException;
import java.util.*;
public class HeapSort 
{
    static  int heapsize;
    public static void main(String args[])
    {
        Vector<Integer> container = new Vector<Integer>(); // container used to store txt file integers
        Scanner myScanner = new Scanner("foo"); // variable used to read file
        String userinput="data1.txt";

        try
        {
            //open filename
            //got problem , must think how to do relative path instead of absolute path
             File inputfile = new File("C:\Users\8382c\workspace\AdvanceAlgorithmA3_Heapsort\src\" + userinput);
             myScanner = new Scanner(inputfile);
        }
        catch(FileNotFoundException e)
        {
            System.out.println("File cant be found");
        }

        String line = myScanner.nextLine(); //read 1st line which contains the number of numbers to be sorted
        while (myScanner.hasNext())
        {
            container.add(myScanner.nextInt());
        }

        heapsize = container.size();
        System.out.println(heapsize);
        sort(container);
        int x =10;
        /*for (int i=0 ; i < container.size() ; i ++)
        {
            System.out.println(container.get(i));
        }*/

        //http://www.sanfoundry.com/java-program-implement-heap-sort/

    }
      public static void swap(Vector<Integer> container, int i, int j)
      {
            /*int tmp = arr[i];
            arr[i] = arr[j];
            arr[j] = tmp;*/
          int tmp = container.get(i);
          container.set(i, container.get(j));
          container.set(j, tmp);
      }   
      public static void maxheap(Vector<Integer> container, int i) //ensure max number is the parent
        { 
            int left = 2*i ;
            int right = 2*i + 1;
            int max = i;
            if (left <= heapsize && container.get(left) > container.get(i));
                max = left;
            if (right <= heapsize && container.get(right) > container.get(max))        
                max = right;
            if (max != i)
            {
                swap(container, i, max);
                maxheap(container, max);
            }
        } 
        public static void heapify(Vector<Integer> container)  //built a heap
        {
            heapsize = container.size()-1;
            for (int i = heapsize/2; i >= 0; i--)
                maxheap(container, i);        
        }

        public static void sort(Vector<Integer> container)
        {       
            heapify(container);        
            for (int i = heapsize; i > 0; i--)
            {
                swap(container,0, i);
                heapsize = heapsize-1;
                maxheap(container, 0);
            }
        }  

}

我已经读取了一个文本文件(忽略文本文件的第一行,它表示条目数),其中包含10000个数字到一个向量,并试图对其进行排序,但我得到以下错误

java.lang.ArrayIndexOutOfBoundsException: Array index out of range: 19998

我的调试器不工作,因为每次我跳过函数max heap,我得到未找到的未解决的源。

我不明白数组越界错误是从哪里产生的,我已经看了过去2小时的实现代码,找不到任何问题,有人能告诉我我的代码有什么问题吗?

行尾有一个分号:

            if (left <= heapsize && container.get(left) > container.get(i));

这意味着下一行总是在运行,而不仅仅是在条件为真时。去掉分号,就可以开始了!

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