#include <iostream>

using namespace std;

int main(void)
{
    int n = 15;
    int arr[n];
    arr[0] = 10;
    cout << "Size: " << sizeof(arr) / sizeof(int) << endl;
    return 0;
}

这样也行啊，卧槽

http://blog.csdn.net/sxhelijian/article/details/16972221

http://bbs.csdn.net/topics/390852247