using System;
using static System.Console;
using static System.Math;

public class Hello{
    public static void Main(){
        string[] input = ReadLine().Split(' ');
        int n = int.Parse(input[0]);
        int x = int.Parse(input[1]);
        if(x>200000){
            WriteLine("0");
        }else{
            string[] num = ReadLine().Split(' ');
            long[] count = new long[300000];
            for(int i=0;i<n;i++){
                int temp = int.Parse(num[i]);
                count[temp]++;
            }
            long ans = 0;
            for(int i=0;i<=x;i++){
                int j = x-i;
                ans += count[i] * count[j];
            }
            WriteLine(ans);
        }
    }
}