c语言如何动态输入一组值

c语言这个动态区如何动态输入值，我这个scanf那一行不对，不能直接用指针的地址吗

#include <stdio.h>
int main()
{
    int* p;
    p = (int*)malloc(100 * sizeof(int));
    int* q = p;
    for (int i = 99; i >= 0; i--)
    {
        *p = i;
        p++;
    }
    p = q;
    int sum = 0;
    while (*p != 0)
    {
        sum += *p;
        p++;
    }
    float ad = (sum * 1.0) / 100;
    printf("%0.2f \n", ad);
    free(q);
    return 0;
}

vs得用printf_s