# 一体版
import numpy as np
from numpy.fft import rfft,irfft

def add(A,B):
    if len(A)<len(B): A,B = B,A
    out = A[:]
    for i in range(-1,-len(B)-1,-1):
        out[i] += B[i]
    return out

def convolve(a1,a2,pad=True):
    n = 2**(len(a1)+len(a2)+1).bit_length()
    b1,b2=np.zeros(n),np.zeros(n)
    b1[:len(a1)], b2[:len(a2)]= a1,a2
    if pad:
      return np.trim_zeros((irfft(rfft(b1)*rfft(b2))+0.5).astype(int), 'b')
    else:
      return (irfft(rfft(b1)*rfft(b2))+0.5).astype(int)

def power(A, k):
    nzero = len(A)-len(np.trim_zeros(A,"f"))
    coef = [A[::-1]]
    out = [1]
    for i in range(k.bit_length()):
        coef.append(convolve(coef[-1], coef[-1]))
        if (k>>i)&1:
            out = convolve(out, coef[-2])
    return np.hstack([np.zeros(nzero*k,dtype=int),out[::-1]])

def div(A, B):
    Q = []
    for i in range(max(len(A)-len(B)+1, 0)):
        Q.append(A[i] /B[0])
        for j in range(len(B)):
            A[i+j] -= Q[-1]*B[j]
    R = []
    for i in range(len(A)):
        if A[i]: 
            R = A[i:]
            break
    if not Q: Q = [0]
    if not R: R = [0]
    return Q,R
  
N,X = map(int,input().split())
*A,=map(int,input().split())

B = np.zeros(10**5+5,dtype=int)

for i in range(N):
  B[A[i]] += 1
  
B = np.trim_zeros(B,"b")

C = convolve(B,B)

print(C[X] if X < len(C) else 0)