def updic(val,dic):
    if val in dic:
        dic[val] += 1
    else:
        dic[val]=1
N,C = map(int,input().split())
x = input()
a = []; j = 0; dic = {}
for i in range(len(x)):
    if x[i] == " ":
        a.append(int(x[i-j:i]))
        updic(a[-1],dic)
        j=0
    else:
        j += 1
a.append(int(x[i-j+1:i+1]))  #思考：这行代码的功能是什么？
updic(a[-1], dic)

ans = 0
for k in dic:
    t = k-C
    if t in dic:
        ans += dic[t]*dic[k]
print(ans)