Dima got into number sequences. Now he's got sequence *a*<sub class="lower-index">1</sub>, *a*<sub class="lower-index">2</sub>, ..., *a*<sub class="lower-index">*n*</sub>, 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* &lt; *j* ≤ *n*) are there, such that *f*(*a*<sub class="lower-index">*i*</sub>) = *f*(*a*<sub class="lower-index">*j*</sub>). Help him, count the number of such pairs.
The first line contains integer *n* (1 ≤ *n* ≤ 10<sup class="upper-index">5</sup>). The second line contains *n* positive integers *a*<sub class="lower-index">1</sub>, *a*<sub class="lower-index">2</sub>, ..., *a*<sub class="lower-index">*n*</sub> (1 ≤ *a*<sub class="lower-index">*i*</sub> ≤ 10<sup class="upper-index">9</sup>).

The numbers in the lines are separated by single spaces.
def f(x):
	return str(bin(x)).count('1')

n = int(input())
a = list(map(int, input().split()))

ans = [f(x) for x in a]
# print(ans)	
s = set(ans)
counts = {x:ans.count(x) for x in s}
# print(counts)
count = 0

for item in counts:
	count += (counts[item]*(counts[item]-1))//2

print(count)			