from collections import *

N, P = map(int, input().split())
A = list(map(int, input().split()))
now = 1
ans = 0
for _ in range(35):
    now *= P
    D = defaultdict(int)
    for i in range(N):
        D[A[i]%now] += 1
    for k, v in D.items():
        ans += v * (v - 1) // 2
print(ans)