import java.util.*;


public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int x = sc.nextInt();
        int[] an = new int[n];
        an = new int[n];
        int ans = 0;
        for (int i = 0; i < n; i++) {
            int a = sc.nextInt();
            an[i] = a;
        }
        if (an[0] + an[0] == x) {
            ans = -1;
        }
        for (int i = 0; i < n; i++) {
            for (int i2 = 0; i2 < n; i2++) {
                if (an[i] + an[i2] == x) {
                    ans++;
                }
            }
        }
        System.out.println(ans);
    }
}