用c语言实现一个链表，使其内部数据为不定长多维数据，并实现对它的初始化，求数据元素个数，插入、删除、取数据元素，判断为非空操作。且对多维数字进行均值滤波、上采样、下采样

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以下是使用 C 语言实现链表的代码，其中链表中的数据元素为不定长多维数据：

#include <stdio.h>
#include <stdlib.h>

typedef struct Node {
    void* data;
    struct Node* next;
} Node;

typedef struct List {
    Node* head;
    int size;
} List;

List* createList() {
    List* list = (List*)malloc(sizeof(List));
    list->head = NULL;
    list->size = 0;
    return list;
}

void insert(List* list, void* data) {
    Node* node = (Node*)malloc(sizeof(Node));
    node->data = data;
    node->next = list->head;
    list->head = node;
    list->size++;
}

void* get(List* list, int index) {
    if (index < 0 || index >= list->size) {
        return NULL;
    }
    Node* node = list->head;
    for (int i = 0; i < index; i++) {
        node = node->next;
    }
    return node->data;
}

void removeNode(List* list, int index) {
    if (index < 0 || index >= list->size) {
        return;
    }
    Node* node = list->head;
    if (index == 0) {
        list->head = node->next;
        free(node);
        list->size--;
        return;
    }
    for (int i = 0; i < index - 1; i++) {
        node = node->next;
    }
    Node* temp = node->next;
    node->next = temp->next;
    free(temp);
    list->size--;
}

int getSize(List* list) {
    return list->size;
}

int isNotEmpty(List* list) {
    return list->size > 0;
}

void initList(List* list) {
    list->head = NULL;
    list->size = 0;
}

// 均值滤波
void meanFilter(List* list) {
    Node* node = list->head;
    while (node != NULL) {
        int* data = (int*)node->data;
        int size = getSize(list);
        for (int i = 0; i < size; i++) {
            data[i] = (data[i] + ((i > 0) ? data[i - 1] : 0) + ((i < size - 1) ? data[i + 1] : 0)) / 3;
        }
        node = node->next;
    }
}

// 上采样
void upsample(List* list) {
    Node* node = list->head;
    while (node != NULL) {
        int* data = (int*)node->data;
        int size = getSize(list);
        int* newData = (int*)malloc(sizeof(int) * size * 2);
        for (int i = 0; i < size; i++) {
            newData[i * 2] = data[i];
            newData[i * 2 + 1] = (i < size - 1) ? (data[i] + data[i + 1]) / 2 : data[i];
        }
        node->data = newData;
        node = node->next;
    }
}

// 下采样
void downsample(List* list) {
    Node* node = list->head;
    while (node != NULL) {
        int* data = (int*)node->data;
        int size = getSize(list);
        int* newData = (int*)malloc(sizeof(int) * (size + 1) / 2);
        for (int i = 0; i < size; i += 2) {
            newData[i / 2] = data[i];
        }
        node->data = newData;
        node = node->next;
    }
}

以上是链表的实现代码，其中均值滤波、上采样、下采样的实现也已经包含在内。

如果您有任何问题或需要进一步的帮助，请随时告诉我。