用C语言根据void MergeSort(int* a, int begin, int end, int* temp)写出归并排序函数

void MergeSort(int* a, int begin, int end, int* temp) {
if (begin >= end) return;

int mid = (begin + end) / 2;
MergeSort(a, begin, mid, temp);
MergeSort(a, mid + 1, end, temp);

int i = begin, j = mid + 1, k = 0;
while (i <= mid && j <= end) {
if (a[i] <= a[j]) {
temp[k++] = a[i++];
} else {
temp[k++] = a[j++];
}
}
while (i <= mid) temp[k++] = a[i++];
while (j <= end) temp[k++] = a[j++];

for (i = 0; i < k; i++) {
a[begin + i] = temp[i];
}
}

相关问题

void mergeSort(int* nums, int begin, int end) { if (begin >= end) { return; } int len = end - begin+1; int mid = begin + (end - begin) / 2; mergeSort(nums, begin, mid); mergeSort(nums, mid+1, end); int* temp = new int[len]; temp = { 0 }; int l1 = begin, r1 = mid; int l2 = mid+1, r2 = end; int i = begin; for (; l1 <= r1 && l2 <= r2;) { if (nums[l1] < nums[l2]) { temp[i++] = nums[l1++]; } else { temp[i++] = nums[l2++]; } } for (; l1 <= r1;) { temp[i++] = nums[l1++]; } for (; l2 <= r2;) { temp[i++] = nums[l2++]; } for (int j = 0; j < len; j++) { nums[j+begin] = temp[j]; } } 出现读取访问冲突，修改代码

在代码中，`temp`被赋值为一个新的`int`数组，然后又被赋值为`{0}`，这样会导致`temp`指向了一个新的内存地址，原有的内存地址被泄漏。在后续的代码中，程序又对这个新的内存地址进行了读写操作，从而导致了读取访问冲突。为了解决这个问题，应该在申请`int`数组的同时，将数组中的元素全部初始化为0。修改后的代码如下：

void mergeSort(int* nums, int begin, int end) {
    if (begin >= end) {
        return;
    }
    int len = end - begin+1;
    int mid = begin + (end - begin) / 2;
    mergeSort(nums, begin, mid);
    mergeSort(nums, mid+1, end);

    int* temp = new int[len](); // 将数组中的元素全部初始化为0
    int l1 = begin, r1 = mid;
    int l2 = mid+1, r2 = end;
    int i = begin;
    for (; l1 <= r1 && l2 <= r2;) {
        if (nums[l1] < nums[l2]) {
            temp[i++] = nums[l1++];
        }
        else {
            temp[i++] = nums[l2++];
        }
    }
    for (; l1 <= r1;) { temp[i++] = nums[l1++]; }
    for (; l2 <= r2;) { temp[i++] = nums[l2++]; }

    for (int j = 0; j < len; j++) {
        nums[j+begin] = temp[j];
    }

    delete[] temp; // 释放动态申请的内存空间
}

以下代码采用分而治之算法实现归并排序。请补充函数mergesort（）的代码。提示：mergesort（）函数可用递归实现，其中参数n在递归调用中不需要变化。 函数接口定义： void mergesort(int a[],int n,int left,int right)；

void merge(int a[], int left, int mid, int right) {
    int i = left;
    int j = mid + 1;
    int k = 0;
    int* tmp = new int[right - left + 1];
    while (i <= mid && j <= right) {
        if (a[i] <= a[j]) {
            tmp[k++] = a[i++];
        }
        else {
            tmp[k++] = a[j++];
        }
    }
    while (i <= mid) {
        tmp[k++] = a[i++];
    }
    while (j <= right) {
        tmp[k++] = a[j++];
    }
    for (int x = 0; x < k; x++) {
        a[left + x] = tmp[x];
    }
    delete[] tmp;
}

void mergesort(int a[], int n, int left, int right) {
    if (left < right) {
        int mid = (left + right) / 2;
        mergesort(a, n, left, mid);
        mergesort(a, n, mid + 1, right);
        merge(a, left, mid, right);
    }
}