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Java中的quicksort代码无法正常运行？

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我从现在开始就一直停留在此...数组未正确排序，并且末尾没有递减，有人可以帮我解决我在这里犯的错误吗？ 我尝试并寻找了几个小时，但找不到确切的错误。您可以在输出中清楚地看到end没有递减并且数组的排序不合适，因为17是倒数第二个元素，而45是倒数第二个元素。另外还有ArrayOutOfBounds的错误。

代码：

     public class Program{

    public static void main(String[] args) {
    int [] ar={4,5,6,3,10,12,45,17};
    int l=0;
    int h=ar.length-1;

    quickSort(ar,l,h);


}
    static void quickSort(int [] arr,int lb,int ub){
    int z;
    if(lb<ub){
    z=partition(arr,lb,ub);
    quickSort(arr,z-1);
    quickSort(arr,z+1,ub);
    }

    for(int i=0;i<arr.length;i++){
        System.out.println(arr[i]);
    }
}


static int partition(int [] a,int ub){
    int pivot=a[lb];
    int start=lb;
    int end=ub;
   //If I put end=ub-1 here then it shows index-1. 
   //so I have not options left to do that the Error is coming eitherway.
    System.out.println("start is "+start);
    System.out.println("End is "+end);

    while(start<end){
        while(a[start]<=pivot){
            start++;
        }
        while(a[end]>pivot){
            end--;
        }
        if(start<end){
        int temp0=a[start];
        int temp1=a[end];
        a[start]=temp1;
        a[end]=temp0;
        }

    }
        int temp2=a[lb];
        int temp3=a[end];
        a[lb]=temp3;
        a[end]=temp2;
        return end;
}
}

output:
start is 0
End is 7
3
4
6
5
10
12
45
17
start is 2
End is 7
3
4
5
6
10
12
45
17
start is 4
End is 7
3
4
5
6
10
12
45
17
start is 5
End is 7
3
4
5
6
10
12
45
17
start is 6
End is 7


Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: Index 8 out of bounds for length 8
    at Program.partition(Program.java:35)
    at Program.quickSort(Program.java:16)
    at Program.quickSort(Program.java:18)
    at Program.quickSort(Program.java:18)
    at Program.quickSort(Program.java:18)
    at Program.quickSort(Program.java:18)
    at Program.main(Program.java:9)
a665362 回答：Java中的quicksort代码无法正常运行？
    class QuickSort 
{ 
    int partition(int arr[],int low,int high) 
    { 
        int pivot = arr[high]; 
        int i = (low-1); // index of smaller element 
        for (int j=low; j<high; j++) 
        { 
            // If current element is smaller than the pivot 
            if (arr[j] < pivot) 
            { 
                i++; 

                // swap arr[i] and arr[j] 
                int temp = arr[i]; 
                arr[i] = arr[j]; 
                arr[j] = temp; 
            } 
        } 

        // swap arr[i+1] and arr[high] (or pivot) 
        int temp = arr[i+1]; 
        arr[i+1] = arr[high]; 
        arr[high] = temp; 

        return i+1; 
    } 

    void sort(int arr[],int high) 
    { 
        if (low < high) 
        { 
            /* pi is partitioning index,arr[pi] is 
            now at right place */
            int pi = partition(arr,low,high); 

            // Recursively sort elements before 
            // partition and after partition 
            sort(arr,pi-1); 
            sort(arr,pi+1,high); 
        } 
    } 

    /* A utility function to print array of size n */
    static void printArray(int arr[]) 
    { 
        int n = arr.length; 
        for (int i=0; i<n; ++i) 
            System.out.print(arr[i]+" "); 
        System.out.println(); 
    } 

    // Driver program 
    public static void main(String args[]) 
    { 
        int arr[] = {4,5,6,3,10,12,45,17}; 
        int n = arr.length; 

        QuickSort ob = new QuickSort(); 
        ob.sort(arr,n-1); 

        System.out.println("sorted array"); 
        printArray(arr); 
    } 
}

输出： 排序数组 3 4 5 6 10 12 17 45

上面的代码适用于您定义的数组，您可以使用此代码。如果您仍然对快速排序感到困惑，可以随意在注释中提问。

algorithmjavaquicksortsorting
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