归并排序模板

void merge_sort(int q[], int L, int R)
{
    if (L >= R)return;//递归中止条件
    int mid =(L + R) >> 1;
    merge_sort(q, L, mid);
    merge_sort(q, mid + 1,R);//先递归处理左右
    int l = L; int r = mid + 1;
    int n = 0;
    while (l <= mid && r <= R)
    {
        if (q[l] <= q[r])
            Temp[n++] = q[l++];
        else
            Temp[n++] = q[r++];
    }
    while (l <= mid)Temp[n++] = q[l++];
    while (r <= R)Temp[n++] = q[r++];
    for (int i = L,j = 0; L <= R;L++,j++)//数据导入
        q[L] = Temp[j];
}
注意归并排序需要额外一个数组Temp来暂时存储结果

注意归并的for循环还有while里不要多写++，否则会出错误的