from collections import defaultdict
n, p = map(int, input().split())
a = list(map(int, input().split()))
t = 1
ans = 0
while t <= 10 ** 10:
    t *= p
    d = defaultdict(int)
    for x in a:
        d[x % t] += 1
    for v in d.values():
        ans += v * (v - 1) // 2
print(ans)