from collections import Counter

def calc(N, X, a):
    cnt = 0
    b = Counter(a)
    for i in range(N):
        cnt += b[X - a[i]]
    return cnt

def main():
    N, X = map(int, input().split())
    a = list(map(int, input().split()))
    print(calc(N, X, a))

if __name__ == '__main__':
    main()