OJ Board

this is my code , each time I submit this problem i got WA :x , please anyone helps me
#include<iostream>
using namespace std;
int main()
{
int n, product[18] = {0}, counter = 1;
long long res;
while(cin >> n)
{
res = 1;
for(int i = 0; i < n; i ++)
cin >> product[i];

for(int i = 0; i < n ...