c - 特定数组的大小

Question

我有一个算法，可以显示两个数组是否相似。它有效，但我不知道数组的大小应该是多少。

例如:

int a[10], i = 0, r = 0, n = 0;
printf("Enter the amount of numbers in arrays: ";
scanf("%d", &n);

printf("Enter the numbers of array: ";
for (i = 0; i < n; i++)
{
   scanf("%d", &a[i]);
}

如果我输入“n”变量 n = 11，程序会在最后停止。我的问题是:我应该在数组 a[THAT_PLACE] 中输入多少数字才能确保该程序与大多数硬件兼容(我听说这也取决于内存。)

@更新1:

我选择了alk 的解决方案。但它仍然不起作用。这是我的代码:

int main()
{

int i = 0, temp_a = 0, switch_a = 0, temp_b = 0, switch_b = 0, n = 0;

printf("Enter the amount of numbers in arrays: ");
scanf("%d", &n);
{
    int a[n], b[n];
    printf("Enter elements of first array: ");
    for (i = 0; i < n; ++i)
    {
        scanf("%d", &a[i]);
    }
    printf("Enter elements of second array:  ");
    for (i = 0; i < n; ++i)
    {
        scanf("%d", &b[i]);
    }
    do
    {
        switch_a = 0;
        for (i = 0; i < n - 1; i++)
        {
            if (a[i] > a[i + 1])
            {
                switch_a = switch_a + 1;
                temp_a = a[i];
                a[i] = a[i + 1];
                a[i + 1] = temp_a;
            }
        }
    } while (switch_a != 0);
    //bubble sort
    do
    {
        switch_b = 0;
        for (i = 0; i < n - 1; i++)
        {
            if (b[i] > b[i + 1])
            {
                switch_b = switch_b + 1;
                temp_b = b[i];
                b[i] = b[i + 1];
                b[i + 1] = temp_b;
            }
        }
    } while (switch_b != 0);
    //Cheks, if an arrays are the same. 
    for (i = 0; i < n; i++)
    {
        if (a[i] != b[i])
        {
            printf("This two arrays don't have the same elements.\n\n\n");
            return 0;
        }
    }

    printf("This two arrays have the same elements.\n\n\n");
}

return 0;

你能帮我查一下吗？我找不到问题所在...

Answer 1

如果您不能(或不想)使用 VLA，请使用 malloc:man malloc

例子:

int *buffer;
int dim;

printf("Enter the amount of numbers in arrays: ");
scanf("%d", &dim);
buffer = (int*) malloc(sizeof(int) * dim);
if (buffer == NULL) {
   perror("Malloc error");
   exit(-1);
}

更多关于 malloc 的信息:Stack Overflow: How do malloc() and free() work?