import collections
N,P = map(int, input().split())
A = list(map(int, input().split()))
ans = 0
for i in range(1,50):
    p = P**i
    C = collections.Counter()
    for a in A:
        C[a%p]+=1
    for k,v in C.items():
        ans+=v*(v-1)//2

print(ans)