Question

我每次添加链接列表后都会打印它。问题是它只打印最近添加的节点。用户应该输入用于创建节点的字符串，然后将该节点添加到列表中。这是代码：

int main() {
    char userChoice = printMenu();
    int setNumber;

    while (userChoice != 'q') {
        printf("set: ");
        scanf("%d", &setNumber);

        Node **nodeArray;
        nodeArray = malloc(10 * sizeof(Node *));

        int i;
        for (i = 0; i < 10; i++) {
            nodeArray[i] = malloc(sizeof(Node));    
        }

        if (userChoice == 'a') 
            add(&nodeArray, setNumber);
        else 
            printf("Please enter a valid menu option.");

        //printf("%s\n", (nodeArray[setNumber]->next)->data);

        userChoice = printMenu();
    }

void add(Node ***nodeArray, int setNumber) {
        char userString[5];
        printf("Please enter some data: ");
        scanf("%s", userString);

        Node *head = *nodeArray[setNumber];     /* head pointer to first element of array (dummy) */
        Node *newNode = malloc(sizeof(Node));   /* new node to be added to array */

        strncpy(newNode->data, userString, sizeof(newNode->data));  /* copies string entered by the user to data field of new node */
        newNode->next = NULL;   /* initializes next field of new node to NULL */

        while (head->next) 
            head = head->next;      /* points head to next element in list */
        head->next = newNode;   /* adds element to list */

        head = *nodeArray[setNumber];   /* points head back to start of list */
        Node *tmp = head;       

        printf("List is: ");
        while (tmp->next) {
            printf("%s", tmp->data);
            tmp = tmp->next;
        }
}

举个例子，当我输入“one”时，它打印出“one”。然后，当我添加“两个”时，它只打印出两个而不是打印出“一个两个”。我做错了什么？

Answer 1

此*nodeArray[setNumber]表示*(nodeArray[setNumber])，但您似乎是(*nodeArray)[setNumber]。或者更好的是，不要将&nodeArray传递给add()，只需通过nodeArray即可。所以：

add(nodeArray, setNumber);
...
void add(Node **nodeArray, int setNumber) {
...
Node *head = nodeArray[setNumber];

Answer 2

问题是每次进入循环时都会创建一个新的内存块。剪切并粘贴在循环外部创建数组的代码，一切都应该正常工作。

打印链接列表仅打印C中的最新数据条目

2 个答案: