C++:合并排序问题:超出范围?

(C++) 大家好,这是我第一次尝试合并。我看到我的代码类似于之前发布问题的人: here . 在较低的级别,排序按预期工作。然而,我认为我这里的问题是,排序后的数组在每个较低级别之后都超出了范围,因此永远不会正确排序。 在这种情况下,我尝试使用“std::vector&”传递引用。我错了吗?通过引用传递的正确方式是什么?

以下是我的代码:

/*
MERGE SORT
breaking down the sorting into pairs concursively until we are comparing only two values
The two integers parameters denotes indices for beginning and ending values in vector
Merge sort inclusive of both left and right range
*/
#include <vector> // for using vectors in c++
void merge(std::vector<int>& inputv, int beg_i, int end_i)
{
    int d = beg_i;  // used as an index
    int e = beg_i + (end_i - beg_i)/2 + 1;  // used as an index

    int y = beg_i + (end_i - beg_i)/2;     // used as a check against d
    int z = end_i;  // used as a check against e

    std::vector<int> tempvect(inputv.size());

    for (int c = beg_i; c < z+1; c++)
    {
        if (e > z && d > y)
        {
            // do nothing
        }
        else if (e > z)
        {
            tempvect[c] = inputv[d];
            d++;
        }
        else if (d > y)
        {
            tempvect[c] = inputv[e];
            e++;
        }

        else if(inputv[d] > inputv[e])
        {
            tempvect[c] = inputv[e];
            e++;
        }
        else if(inputv[d] <= inputv[e])
        {
            tempvect[c] = inputv[d];
            d++;
        }
    }
    for (int i = beg_i; i < end_i+1; i++)
    {
        inputv[i] = tempvect[i];
    }
}

void mergesort(std::vector<int> inputvector, int beg_i, int end_i)
{
    if(end_i - beg_i == 0) 
    {
        // do nothing
    }
    if(end_i - beg_i >= 1)
    {
        int mid_i = beg_i + (end_i - beg_i)/2;

        mergesort(inputvector,beg_i,mid_i); // reclusive to last card
        mergesort(inputvector,mid_i+1,end_i);   // resulsive to last card
        merge(inputvector,beg_i,end_i); // actual implementation to sort and merge the vectors
    }

}