using System;
using System.IO;
using System.Collections.Generic;
using System.Linq;

namespace No723
{
    public class Program
    {
        void Solve(StreamScanner ss, StreamWriter sw)
        {
            //---------------------------------
            var N = ss.Next(int.Parse);
            var X = ss.Next(long.Parse);
            var A = ss.Next(long.Parse, N).OrderBy(x => x).ToArray();

            var bs = A.GetBinarySearch();
            var ret = 0L;
            for (var i = 0; i < N; i++) ret += bs.SetFunc(x => A[x] + A[i]).Count(X);
            sw.WriteLine(ret);
            //---------------------------------
        }

        static void Main()
        {
            var ss = new StreamScanner(new StreamReader(Console.OpenStandardInput()));
            var sw = new StreamWriter(Console.OpenStandardOutput()) {AutoFlush = false};
            new Program().Solve(ss, sw);
            sw.Flush();
        }
    }

    public static partial class BinarySearch
    {
        public static BinarySearch<T> Default<T>(Func<long, T> func, long left, long right) where T : IComparable<T>
        {
            return new BinarySearch<T>().SetFunc(func).SetInterval(left, right);
        }

        public static BinarySearch<T> Array<T>(T[] array) where T : IComparable<T>
        {
            return new BinarySearch<T>().SetFunc(x => array[x]).SetInterval(0, array.Length);
        }

        public static BinarySearch<T> GetBinarySearch<T>(this T[] source) where T : IComparable<T>
        {
            return Array(source);
        }
    }

    public class BinarySearch<T> where T : IComparable<T>
    {
        Func<long, T> Func { get; set; } = null;
        long Left { get; set; } = 0;
        long Right { get; set; } = 0;
        bool IsOrderAscending { get; set; } = true;

        public BinarySearch<T> SetFunc(Func<long, T> func)
        {
            Func = func;
            return this;
        }

        public BinarySearch<T> SetInterval(long left, long right)
        {
            if (left > right) throw new ArgumentException($"{nameof(left)} <= {nameof(right)}");
            Left = left;
            Right = right;
            return this;
        }

        public BinarySearch<T> SetOrder(bool isOrderAscending)
        {
            IsOrderAscending = isOrderAscending;
            return this;
        }

        long BoundToTheRight(Func<long, bool> pred, long left, long right)
        {
            while (true)
            {
                if (left == right) return right;
                var mid = (left + right - 1) >> 1;
                if (pred(mid)) right = mid;
                else left = mid + 1;
            }
        }

        public long LowerBound(T value)
        {
            var sign = IsOrderAscending ? 1 : -1;
            return BoundToTheRight(x => sign * Func(x).CompareTo(value) >= 0, Left, Right);
        }

        public long UpperBound(T value)
        {
            var sign = IsOrderAscending ? 1 : -1;
            return BoundToTheRight(x => sign * Func(x).CompareTo(value) > 0, Left, Right);
        }

        public long Range(T vLeft, T vRight)
        {
            return Math.Max(0, UpperBound(vRight) - LowerBound(vLeft));
        }

        public long Count(T value)
        {
            return Range(value, value);
        }
    }

    public class StreamScanner
    {
        static readonly char[] Sep = {' '};
        readonly Queue<string> buffer = new Queue<string>();
        readonly TextReader textReader;

        public StreamScanner(TextReader textReader)
        {
            this.textReader = textReader;
        }

        public T Next<T>(Func<string, T> parser)
        {
            if (buffer.Count != 0) return parser(buffer.Dequeue());
            var nextStrings = textReader.ReadLine().Split(Sep, StringSplitOptions.RemoveEmptyEntries);
            foreach (var nextString in nextStrings) buffer.Enqueue(nextString);
            return Next(parser);
        }

        public T[] Next<T>(Func<string, T> parser, int x)
        {
            var ret = new T[x];
            for (var i = 0; i < x; ++i) ret[i] = Next(parser);
            return ret;
        }

        public T[][] Next<T>(Func<string, T> parser, int x, int y)
        {
            var ret = new T[y][];
            for (var i = 0; i < y; ++i) ret[i] = Next(parser, x);
            return ret;
        }
    }
}