为何出错？

#include<iostream>
using namespace std;
const int ArSize = 8;

int main()
{
int a=0;
int cookie[ArSize] ;
for (int i =1; i < ArSize+1; i++)
{
cout << "Enter the " << i << " number :";
cin >> cookie[i];
        a += cookie[i];
}

cout << "Total is" << a << endl;

}