#include<iostream>
#include<vector>
#include<algorithm>

using namespace std;

bool binary_search(int key,vector<int> a) {
	int left = 0, right = (int)a.size() - 1; // 配列 a の左端と右端
	while (right >= left) {
		int mid = left + (right - left) / 2; // 区間の真ん中
		if (a[mid] == key) return true;//値を返す
		else if (a[mid] > key) right = mid - 1;
		else if (a[mid] < key) left = mid + 1;
	}
	return false;
}


int main() {

	int n, x;
	int count = 0;//数え上げる変数
	cin >> n >> x;
	vector<int> data;
	for (int i = 0;i < n;i++) {
		int buff = 0;
		cin >> buff;
		data.push_back(buff);
	}
	sort(data.begin(),data.end());
	for (int i = 0;i < n;i++) {
		int target = x - data[i];
		if (binary_search(target, data))count++;
	}
	cout << count << endl;

	return 0;
}