from collections import defaultdict

def main():
    N, X = map(int, input().split())
    A = list(map(int, input().split()))
    d = defaultdict(int)
    for a in A:
        d[a] += 1
    ans = 0
    for a in A:
        tmp = X - a
        ans += d[tmp]
    print(ans)



if __name__ == "__main__":
    main()