Question

谁会知道为什么我的就地合并排序是“索引超出范围” ？

最初，我的“ low”值为0，但是我决定对每个“ low，mid，high”值执行+1，以补偿索引空间。谁能找到任何东西？谢谢。

def merge(array, low, mid, high):

    i,j,k = low,mid+1,low
    leftarray = array[low:mid+1]
    rightarray = array[mid+1:high+1]

    temp= [0]*high

    while i<=mid and j<=high:

        if array[i]<array[j]:
            temp[k] = array[i]
            i+=1
        else:
            temp[k] = array[j]
            j+=1
        k+=1

    if i>mid:
        temp[k:high+1] = array[j:high+1]
    else:
        temp[k:high+1] = array[i:mid+1]  

    array[low:high+1] = temp[low:high+1]

    def inplace(array,low,high):

        if low<high:
            mid = int((low+high)/2)
            inplace(array,low,mid)
            inplace(array,mid+1,high)
            merge_test(array,low,mid,high)


    array = [20,30,21,15,42,45,31,0,9]
    inplace(array, 0, len(array)-1)
    print(array)

Answer 1

您的代码中存在错误，此部分的缩进不正确。它应该在while循环之外。一旦合并完成。 请参阅合并排序伪代码以查找错误所在。

if i>mid:
    temp[k:high+1] = array[j:high+1]
else:
    temp[k:high+1] = array[i:mid+1]  

array[low:high+1] = temp[low:high+1]

以下代码正在工作。

def merge_test(array, low, mid, high):

    i,j,k = low,mid+1,low
    leftarray = array[low:mid+1]
    rightarray = array[mid+1:high+1]

    temp= [0]*high

    while i<=mid and j<=high:

        if array[i]<array[j]:
            temp[k] = array[i]
            i+=1
        else:
            temp[k] = array[j]
            j+=1
        k+=1


    if i>mid:
        temp[k:high+1] = array[j:high+1]
    else:
        temp[k:high+1] = array[i:mid+1]  

    array[low:high+1] = temp[low:high+1]


def inplace(array,low,high):

    if low<high:
        mid = int((low+high)/2)
        inplace(array,low,mid)
        inplace(array,mid+1,high)
        merge_test(array,low,mid,high)


array = [20,30,21,15,42,45,31,0,9]
inplace(array, 0, len(array)-1)
print(array)

输出：

[0, 9, 15, 20, 21, 30, 31, 42, 45]

PS：请始终发布完整的错误堆栈跟踪。它有助于调试代码。您还应该尝试读取堆栈跟踪。

Python就地合并排序错误：索引超出范围

1 个答案: