求解为什么这个归并排序得不到正确的结果

#include <stdio.h>


//归并排序算法 

void sort(int *arr, int *carr, int low, int mid, int high)
{
    int i = low; 
    int k = low; 
    int j = mid+1;
    while(i<=mid && j<=high)
    { //将两边小的加进去 
        if(arr[i] < arr[j])
        {
            carr[k++] = arr[i++];
        }
        else 
        {
            carr[k++] = arr[j++];
        }
    }
    
    while(i<=mid) carr[k++] = arr[i++]; //将左边剩余的部分加进去 

    while(j<=high) carr[k++] = arr[j++]; //将右边剩余的部分加进去 
}



void mergerSort(int *arr, int *carr, int low, int high)
{
    int mid = (low + high) / 2;
    if(low<high)
    {
        mergerSort(arr, carr, low, mid);
        mergerSort(arr, carr, mid+1, high);
        sort(arr, carr, low, mid, high);
    }
    else return;
}







int main()
{
    int arr[] = {49,38,65,11,97,13,27,76,101,15};
    int length = sizeof(arr) / sizeof(arr[0]);
    int carr[length] = {0};

    mergerSort(arr, carr, 0, length-1);
    
    for(int i=0; i<length; i++)
    {
        printf("%d ",carr[i]);
    }
    printf("\n");
    return 0;
}

sort最后加几行
for (int i = low; i <= high; i++)
{
arr[i] = carr[i];
}

一次排好的结果要赋值给原数组 否则你每次排序都是从原始数组取值 并没有发生任何改变 结果肯定不对