#include <bits/stdc++.h>
using namespace std;

int a[1 << 18], b[1 << 18], cnt[1 << 18];
long long inv[18][2];

signed main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0); cout.tie(0);
	int n; cin >> n; long long ans = 0, cur;
	for (int i = 1; i <= n; ++i) cin >> a[i], b[i] = a[i];
	for (int bit = 0; bit <= __lg(n); ++bit) {
		for (int i = 1; i <= n; ++i) if (b[i] & (1 << bit)) b[i] ^= (1 << bit);
		for (int i = 0; i < n; ++i) cnt[i] = 0;
		for (int i = 1; i <= n; ++i) 
			if (!(a[i] & (1 << bit))) inv[bit][0] += cnt[b[i]];
			else ++cnt[b[i]];
		for (int i = 0; i < n; ++i) cnt[i] = 0;
		for (int i = 1; i <= n; ++i) 
			if (a[i] & (1 << bit)) inv[bit][1] += cnt[b[i]];
			else ++cnt[b[i]];
		ans += inv[bit][0];
	}
	for (int x = 1; x < n; ++x) {
		cur = 1;
		for (int bit = 0; bit <= __lg(n); ++bit) if (x & (1 << bit)) cur += inv[bit][1];
		ans = min(ans, cur);
	}
	cout << ans;
}