#define _USE_MATH_DEFINES
#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#include<string>
#include<iostream>
#include<iostream>
#include<cctype>
#include<cstdio>
#include<vector>
#include<stack>
#include<queue>
#include <algorithm>
#include<math.h>
#include<set>
#include<map>
#include <sstream>
#include<iomanip>
#include <ctype.h>
using namespace std;

//#include<bits/stdc++.h>
int f[100005];
int main() {
	
	int n, x;
	cin >> n >> x;
	long long int p = 0;
	for (int i = 0; i < n; i++) {
		int a;
		cin >> a;
		f[a]++;
	}

	for (int i = 0; i <= x / 2; i++) {
		if(i!=x/2)p += f[i] * f[x - i]*2;
		else p += f[i] * f[x - i];
		

	}
	cout << p << endl;

	return 0;
}