c语言代码：新建一个顺序表，将输入的数据存入顺序表，并将输入的元素输出，并完成以下操作，1、删除指定位置的元素；2、向指定位置插入元素；3、查找某元素在线性表中的位置；

在C语言中，我们可以使用结构体和指针来创建一个简单的顺序表。下面是一个基本的实现，包括初始化、添加元素、删除元素和查找元素的功能：

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

// 定义顺序表节点结构
typedef struct Node {
    int data;
    struct Node* next;
} Node;

// 创建并初始化顺序表
Node* createList() {
    Node* head = (Node*)malloc(sizeof(Node));
    if (!head) {
        printf("Memory allocation failed.\n");
        return NULL;
    }
    head->data = -1; // 空表标记
    head->next = NULL;
    return head;
}

// 添加元素到列表
void insertElement(Node** head, int value, int position) {
    Node* newNode = (Node*)malloc(sizeof(Node));
    newNode->data = value;
    newNode->next = *head;

    if (position == 0) { // 插入在首位
        *head = newNode;
    } else {
        Node* current = *head;
        for (int i = 1; i < position && current != NULL; i++) {
            current = current->next;
        }
        if (current != NULL) {
            newNode->next = current->next;
            current->next = newNode;
        } else {
            printf("Position out of range.\n");
        }
    }
}

// 删除指定位置的元素
void deleteElement(Node** head, int position) {
    if (*head == NULL) {
        printf("List is empty.\n");
        return;
    }

    Node* current = *head;
    Node* previous = NULL;

    if (position == 0) { // 删除首位
        *head = current->next;
    } else {
        for (int i = 1; i < position && current != NULL; i++) {
            previous = current;
            current = current->next;
        }
        if (current != NULL) {
            previous->next = current->next;
        } else {
            printf("Position out of range.\n");
        }
    }
}

// 查找元素的位置
int findElement(Node* head, int value) {
    Node* current = head;
    int position = 0;

    while (current != NULL) {
        if (current->data == value)
            return position;
        current = current->next;
        position++;
    }

    return -1; // 元素未找到
}

// 打印列表
void printList(Node* head) {
    Node* temp = head;
    while (temp != NULL) {
        printf("%d ", temp->data);
        temp = temp->next;
    }
    printf("\n");
}

int main() {
    Node* listHead = createList();
    
    // 用户输入数据并操作
    int input, choice;
    do {
        printf("Choose an operation:\n");
        printf("1. Insert at position\n");
        printf("2. Delete element by position\n");
        printf("3. Find element\n");
        printf("4. Print list\n");
        printf("5. Exit\n");
        scanf("%d", &choice);

        switch (choice) {
            case 1:
                printf("Enter value and position: ");
                scanf("%d %d", &input, &position);
                insertElement(&listHead, input, position);
                break;
            case 2:
                printf("Enter position to delete: ");
                scanf("%d", &position);
                deleteElement(&listHead, position);
                break;
            case 3:
                printf("Enter value to search: ");
                scanf("%d", &input);
                int pos = findElement(listHead, input);
                if (pos != -1)
                    printf("Element found at position %d.\n", pos);
                else
                    printf("Element not found.\n");
                break;
            case 4:
                printList(listHead);
                break;
            case 5:
                break;
            default:
                printf("Invalid choice.\n");
        }
    } while (choice != 5);

    return 0;
}