#include <iostream>
using namespace std;

class CandyBox {
private:
    int cnt;
    int* candies;
public:
    CandyBox(int cnt = 0) {
        this->cnt = cnt;
        candies = new int[cnt];
    }
    ~CandyBox() {
        delete[] candies;
    }
    CandyBox(const CandyBox& other) {
        cnt = other.cnt;
        candies = new int[cnt];
        for (int i = 0; i < cnt; i++) {
            candies[i] = other.candies[i];
        }
    }
    CandyBox operator[] (int index) const {
        return candies[index];
    }
    int count(int x) {
        int sum = 0;
        for (int i = 0; i < cnt; i++) {
            if (candies[i] == x)
                sum++;
        }
        return sum;
    }
    void read() {
        for (int i = 0; i < cnt; i++) {
            cin >> candies[i];
        }
    }
    void print() {
        for (int i = 0; i < cnt; i++) {
            cout << candies[i] << " ";
        }
    }
    int varieties() {
        int sum = 1;
        for (int i = 0; i < cnt; i++) {
            for (int j = 1; j < cnt; j++) {
                if (candies[j] < candies[j - 1]) {
                    swap(candies[j], candies[j - 1]);

                }
            }
        }
        for (int i = 1; i < cnt; i++) {
            if (candies[i] != candies[i - 1]) {
                sum++;
            }
        }
        return sum;
    }
    int size() {
        this->cnt = cnt;
        return cnt;
    }
    int& at(int index) {
        return candies[index];
    }
};

CandyBox Arcady_process(CandyBox& b) {
    int* arr = new int[b.size()];
    for (int i = 0; i < b.size(); i++) {
        arr[i] = 0;
    }
    int tmp = 0;
    for (int i = 0; i < b.size(); i++) {
        if (b.at(i) % 2 == 0) {
            arr[tmp] = b.at(i);
            b.at(i) = 0;
            tmp++;
        }
    }
    int j = 0;
    for (int i = 0; i < b.size(); i++) {
        if (b.at(i) == 0 && arr[j] != 0) {
            b.at(i) = arr[j];
            j += 2;
        }
    }
    delete[] arr;
    return b;
}

CandyBox Alice_process(CandyBox& b) {
    for (int i = 0; i < b.size() / 2; i++) {
        b.at(i) = 0;
    }
    CandyBox c(b);
    for (int i = 0; i < b.size(); i++) {
        b.at(i) = 0;
    }
    int j = b.size()/2;
    for (int i = 0; i < b.size(); i += 2) {
        b.at(i) = c.at(j);
        j++;
    }
    return b;
}

int count_afterwards(CandyBox& b, int x) {
    CandyBox a(b);
    Alice_process(a);
    Arcady_process(b);
    return a.count(x) + b.count(x);
}

int main() {
    int cnt,x;
    cin >> cnt;
    CandyBox a(cnt);
    a.read();
    cin >> x;
    cout << count_afterwards(a, x);
    return 0;
}