#include #include #include #include #include #include #include #include #include #include #include #include #include #define debug_value(x) cerr << "line" << __LINE__ << ":<" << __func__ << ">:" << #x << "=" << x << endl; #define debug(x) cerr << "line" << __LINE__ << ":<" << __func__ << ">:" << x << endl; template inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; } template inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; } using namespace std; typedef long long ll; template vector> vec2d(int n, int m, T v){ return vector>(n, vector(m, v)); } template vector>> vec3d(int n, int m, int k, T v){ return vector>>(n, vector>(m, vector(k, v))); } template void print_vector(vector v, char delimiter=' '){ if(v.empty()) { cout << endl; return; } for(int i = 0; i+1 < v.size(); i++) cout << v[i] << delimiter; cout << v.back() << endl; } int main(){ ios::sync_with_stdio(false); cin.tie(0); cout << setprecision(10) << fixed; int n; ll p; cin >> n >> p; vector a(n); for(int i = 0; i < n; i++) cin >> a[i]; ll x = p; ll ans = 0; while(true){ vector b(n); map mp; for(int i = 0; i < n; i++) { ll y = a[i]%x; if(mp.count(y)) mp[y]++; else mp[y] = 1; } for(auto [x, c]: mp){ ans += (c*(c-1))/2; } if(x*p > 1e9) break; x *= p; } cout << ans << endl; }