#include <bits/stdc++.h>

using namespace std;

#define FOR(i,a,b) for(int i=(a);i<(b);i++)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) (v).begin(),(v).end()
#define fi first
#define se second

template<typename A, typename B> inline bool chmax(A &a, B b) { if (a<b) { a=b; return 1; } return 0; }
template<typename A, typename B> inline bool chmin(A &a, B b) { if (a>b) { a=b; return 1; } return 0; }

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef pair<int, pll> pip;
const ll INF = 1ll<<60;
const ll MOD = 1000000007;
const double EPS  = 1e-9;

int n;
int a[112345];

int main() {
	while (cin >> n, n) {
		REP(i, n) scanf("%d", a + i);
		
		int k; cin >> k;
		
		int l = 0, r = n - 1;
		int c = 0;
		while (true) {
			int m = (l + r) / 2;
			c++;
			
			if (a[m] == k) break;
			if (r == l) break;
			
			if (a[m] < k) l = m + 1;
			else r = m - 1;
		}
		
		cout << c << endl;
	}
	return 0;
}