#include<cstdio>
#include<algorithm>

#define N 1000

using namespace std;
int mas[N];
int main() {
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
    int n, w, a, k, s, m;
    s = 0;
    scanf("%d", &n);
    for (int i = 0; i < n; i++)
        scanf("%d", &mas[i]);
    scanf("%d", &k);
    int answer = int(1e9);
    for (int j = 0; j < n; j++)
        if (abs(answer - k) > abs(mas[j] - k))
            answer = mas[j];
    printf ("%d", answer);
    return 0;
}