Question

我试图实现程序，我可以动态创建〜任意数量的单链表，并对特定的列表执行操作（由参数定义）。我创建了头指针的动态数组，以便我可以引用由paramater定义的某个头节点（数组的索引+ 1）。参数只是（1,2,3 ......列表）。到目前为止，我已经设法只实现初始化和推送功能，但是在complilation之后的程序并没有按预期工作。问题出在哪儿？

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

#define CHUNK 10

typedef struct
{
    char *str;
    struct node *next;
} node;


node *initialise(node **array, int *amount_of_lists);
void push(node **array, int *amount_of_lists);
char *getString(void);

int main()
{
    node **heads = NULL; //initially null, pointer to the dynamic array of head pointers
    int amount_of_lists = 0;
    int *no_of_heads = &amount_of_lists;

    initialise(heads, no_of_heads);
    initialise(heads, no_of_heads);
    push(heads, no_of_heads);
    push(heads, no_of_heads);

    return 0;
}

node *initialise( node **array, int *amount_of_lists )  /*reallocate memory for another head pointer ans return the pointer to node*/
{
    ++(*amount_of_lists);
    printf("\n%d", *amount_of_lists);
    array = (node**)realloc(array, sizeof(node*)*(*amount_of_lists));
    return array[(*amount_of_lists) - 1] = malloc(sizeof(node));
}

int readParameter(int *amount_of_lists)
{
    int parameter = 0, control = 0;
    bool repeat = 0;
    do
    {
        if(repeat)
        {
            printf("\nWrong parameter, try again.");
        }
        printf("\n Enter list parameter: ");
        control = scanf("%d", &parameter);
        fflush(stdin);
        repeat = 1;
    }
    while( control != 1 || parameter < 1 || parameter > (*amount_of_lists) );

    return parameter;
}

void push(node **array, int *amount_of_lists)
{
    int parameter = readParameter(amount_of_lists) - 1;
    node *temp = array[parameter];
    array[parameter] = malloc(sizeof(node));
    array[parameter] -> next = temp;
    array[parameter] -> str = getString();
}

char *getString(void)
{
    char *line = NULL, *tmp = NULL;
    size_t size = 0, index = 0;
    int ch = EOF;

    while (ch)
    {
        ch = getc(stdin);

        /* Check if we need to stop. */
        if (ch == EOF || ch == '\n')
            ch = 0;

        /* Check if we need to expand. */
        if (size <= index)
        {
            size += CHUNK;
            tmp = realloc(line, size);
            if (!tmp)
            {

                free(line);
                line = NULL;
                break;
            }
            line = tmp;
        }

        /* Actually store the thing. */
        line[index++] = ch;
    }

    return line;
}

Answer 1

正如BLUEPIXY在他的评论1）中有点含糊地暗示，为了修改main()中的heads initialise()，你必须通过heads 通过引用到initialise()，i。即变化

    initialise(heads, no_of_heads);
    initialise(heads, no_of_heads);

到

    initialise(&heads, no_of_heads);
    initialise(&heads, no_of_heads);

因此

node *initialise( node **array, int *amount_of_lists )

更改为

node *initialise(node ***array, int *amount_of_lists)

和array内部更改为*array，i。即

    *array = realloc(*array, sizeof(node *) * *amount_of_lists);
    return (*array)[*amount_of_lists - 1] = malloc(sizeof(node));

链接列表，带参数的操作

1 个答案: