在堆中分配内存以保存指向字符的指针数组时，代码崩溃

Question

#define MAX_STRING_SIZE 256

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


static void getList(char ***pppclist) 
{
    int n=0;
    int i =0;

    printf("Enter the number of items in the List: ");
    scanf("%d", &n);

    //Array of Pointers to characters
    *pppclist = (char **)malloc(n * sizeof(char *));  //X50, x51, x52

    for( i=0; i<=n; i++)
    {
        *(pppclist[i]) = (char *)malloc(MAX_STRING_SIZE * sizeof(char)); //*X50 = X100

        printf("Enter the %d items in the List: ", i);
        scanf("%s", pppclist[i]);
    }

}

main(int argc, char *argv[])
{


    char **ppclist = NULL; //array of Pointer to Pointer to character

    getList(&ppclist); //X1

    printf("The Entered List is:%s", ppclist);



    for(;;);
}

大家好...请帮忙调试上面程序中的错误。我想在 get list 函数中获取一个字符串列表，并将其打印在 main 堆栈中。我已经在堆中分配了内存，用于保存指向字符和字符的指针数组。出了问题。有人可以帮助我吗？PS:不要标记为重复

Answer 1

首先，在getList函数中，当要访问数组中的第n项时，必须将*pppclist括在括号内，而不是*pppclist[i] 因为您应该首先取消引用指针，然后再访问第 n 项。

接下来，当您分配数组时，您应该再分配一项并将其设置为NULL。这对于稍后浏览您的数组很有用。

这是更正后的代码:

#define MAX_STRING_SIZE 256

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


static void getList(char ***pppclist)
{
    int n=0;
    int i =0;

    printf("Enter the number of items in the List: ");
    scanf("%d", &n);

    //Array of Pointers to characters
    *pppclist = (char **)malloc((n + 1) * sizeof(char *));  //X50, x51, x52
    (*pppclist)[n] = NULL;

    for( i=0; i<n; i++)
    {
      (*pppclist)[i] = (char *)malloc(MAX_STRING_SIZE * sizeof(char)); //*X50 = X100

        printf("Enter the %d items in the List: ", i);
        scanf("%s", (*pppclist)[i]);
    }

}

int main(int argc, char *argv[])
{


    char **ppclist = NULL; //array of Pointer to Pointer to character
    int index;

    getList(&ppclist); //X1

    index = 0;
    while (ppclist[index]) {
      printf("The Entered List is:%s\n", ppclist[index]);
      index += 1;
    }

    return (0);
}