Dima got into number sequences. Now he's got sequence a1, a2, ..., an, consisting of n positive integers. Also, Dima has got a function f(x), which can be defined with the following recurrence:

  * f(0) = 0; 
  * f(2·x) = f(x); 
  * f(2·x + 1) = f(x) + 1. 



Dima wonders, how many pairs of indexes (i, j) (1 ≤ i < j ≤ n) are there, such that f(ai) = f(aj). Help him, count the number of such pairs. 

Input

The first line contains integer n (1 ≤ n ≤ 105). The second line contains n positive integers a1, a2, ..., an (1 ≤ ai ≤ 109).

The numbers in the lines are separated by single spaces.

Output

In a single line print the answer to the problem.

Please, don't use the %lld specifier to read or write 64-bit integers in C++. It is preferred to use the cin, cout streams or the %I64d specifier.

Examples

Input

3
1 2 4


Output

3


Input

3
5 3 1


Output

1

Note

In the first sample any pair (i, j) will do, so the answer is 3.

In the second sample only pair (1, 2) will do.
#include <bits/stdc++.h>
using namespace std;
template <class T>
int getbit(int i, T X) {
  return ((X >> (i - 1)) & 1);
}
template <class T>
T onbit(int i, T X) {
  return (X | (1 << (i - 1)));
}
template <class T>
T offbit(int i, T X) {
  return ((X | (1 << (i - 1))) - (1 << (i - 1)));
}
template <class T>
T sqr(T x) {
  return (x * x);
}
template <class T>
T cube(T x) {
  return (x * x * x);
}
template <class T>
T gcd(T a, T b) {
  T r;
  while (b != 0) {
    r = a % b;
    a = b;
    b = r;
  }
  return a;
}
template <class T>
T lcm(T a, T b) {
  return a / gcd(a, b) * b;
}
int csx[4] = {0, 0, -1, 1};
int csy[4] = {-1, 1, 0, 0};
long long n, a[100005], Count[40];
void nhap() {
  cin >> n;
  for (typeof(n) i = 1; i <= n; i++) cin >> a[i];
}
int F(long long K) {
  if (K == 0) return 0;
  if (K % 2) return (F(K / 2) + 1);
  return F(K / 2);
}
void xu_ly() {
  memset(Count, 0, sizeof(Count));
  long long res = 0;
  for (typeof(n) i = 1; i <= n; i++) Count[F(a[i])]++;
  for (typeof(35) i = 0; i <= 35; i++) res += (Count[i] - 1) * Count[i] / 2;
  cout << res;
}
int main() {
  std::ios::sync_with_stdio(false);
  nhap();
  xu_ly();
  return 0;
}
