#include <bits/stdc++.h>
using namespace std;
#define int long long
signed main(){
  int N,P;
  cin>>N>>P;
  int ans = 0;
  vector<int> S(N);
  for(int i=0;i<N;i++) cin>>S[i];
  int p = P;
  while(P < 1e12){
    map<int,int> m;
    for(int i=0;i<N;i++) m[S[i]%P]++;
    for(auto x:m) ans += x.second*(x.second-1)/2;
    P *= p;
  }
  cout<<ans<<endl;
}