include

using namespace std;
int search(int list[], int n, int x);

int main()
{
int a[10];
int i;
int n,x;
cin >> n;
for (i = 0; i < n; i++)
{
cin >> a[i];
}
cin >> x;
cout<<search(a, n, x);
return 0;
}
int search(int list[], int n, int x)
{
int* p;
int count = 0;
p = list;
for (int i = 0; i < n; i++)
{
if (*(p + i) == x)
{
return i;
}
}
if (count == 0)
{
return count;
}
}