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