from collections import defaultdict

N, P = map(int, input().split())
A = list(map(int, input().split()))
P2 = P
maxa = max(A)
ans = 0
while P2 <= maxa:
    dic = defaultdict(int)
    for a in A:
        dic[a % P2] += 1
    for v in dic.values():
        if v > 1:
            ans += v * (v - 1) // 2
    P2 *= P
print(ans)