import java.util.Arrays;
import java.util.Scanner;

public class Main{
    static int N = 2_00_010;
    static int [] a = new int [N];
    static int n;

    //利用双指针，返回a数组中小于等于x的个数
    static long calc(int x) {
        int l = 1, r = n;
        long ans = 0;
        while(l < r)
        {
            while(l < r && a[l] + a[r] > x) {
                r --;
            }

            ans += r - l;
            l ++;
        }

        return ans;
    }

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        n = sc.nextInt();
        int l = sc.nextInt();
        int r = sc.nextInt();

        for(int i = 1; i <= n; i ++) a[i] = sc.nextInt();
        Arrays.sort(a, 1, n + 1);

        System.out.println(calc(r) - calc(l - 1));

    }
}