c - 动态分配char**

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这是我的示例的文本:

Loading number N then N words from standard input. The word is not longer than 100 characters. Dynamically allocate array of loaded words as a series of pointers to character strings (dynamic array needs to have a type char **). Provide a set of words printed in a single line with spaces between the words.

有人可以告诉我如何设置字符限制吗？

我应该这样做吗:

scanf("%100s", str[i])

还是其他什么？
顺便说一句，我如何为这样的类型分配内存( char ** 、 int ** 等)？

这是我完成的代码，那么我做错了什么？

int main()
{
    int i,n;
    printf("How much words? "), scanf("%d", &n);
    char *str= (char *)malloc(n*sizeof(char *));
    for(i = 0; i < n; i++)
    {
        str[i] = malloc(100 * sizeof(char *));
        printf("%d. word: ", i + 1),scanf("%s", str[i]);
    }
    for (i = 0; i < n; i++)
    {
        printf("%s ", str[i]);
    }
    getch();

Answer 1

指针数组类型错误

// char *str
char **str

带有注释的代码清理。

// add void
int main(void) {
    int i,n;
    // Easier to understand if on 2 lines-of code
    printf("How much words? ");
    // test scanf() results
    if (scanf("%d", &n) != 1) return -1;

    // Consider different style to allocate memory, as well as type change
    //  char *str= (char *)malloc(n*sizeof(char *));
    char **str= malloc(sizeof *str * n);
    // check allocation
    assert(str == NULL); 

    for(i = 0; i < n; i++) {
        str[i] = malloc(sizeof *str[i] * 100);
        // check allocation
        assert(str[i] == NULL); 

        printf("%d. word: ", i + 1);
        fflush(stdout);

        // limit input width to 99
        // test scanf() results
        if (scanf("%99s", str[i]) != 1) return -1;
    }
    for (i = 0; i < n; i++) {
        // Add () to clearly show beginning/end of string 
        printf("(%s) ", str[i]);
    }
    getch();
}