using System.Collections.Generic;
using System;

public class hello
{
    public static void Main()
    {
        var d = new Dictionary<int, int>();
        string[] line = Console.ReadLine().Trim().Split(' ');
        var n = int.Parse(line[0]);
        var a = int.Parse(line[1]);
        line = Console.ReadLine().Trim().Split(' ');
        for (int i = 0; i < n; i++)
        {
            var w = int.Parse(line[i]);
            if (d.ContainsKey(w)) d[w]++;
            else d[w] = 1;
        }
        var ans = 0L;
        foreach (var x in d)
        {
            var s = a - x.Key;
            if (x.Key == s) ans++;
            else if (d.ContainsKey(s))
                ans += x.Value * d[s];
        }
        Console.WriteLine(ans);
    }
}