#include <bits/stdc++.h>
#define all(a) begin(a), end(a)
#define int long long
using namespace std;

int a[1 << 18], ai[1 << 18];

struct BIT{
	int bit[1 << 19];
	void add(int p, int v) { ++p; for (int i = p; i < (1 << 19); i += i & -i) bit[i] += v; }
	int qry(int p) { ++p; int ret = 0; for (int i = p; i; i -= i & -i) ret += bit[i]; return ret; }
} bit;

void solve(){
	int n; cin >> n;
	for (int i = 0; i < n; i++) {
		cin >> a[i]; ai[a[i]] = i;
	}
	int inv = 0;
	for (int i = n - 1; i >= 0; i--) {
		inv += bit.qry(a[i]);
		bit.add(a[i], 1);
	}
	int ans = 1;
	for (int b = 0; (1 << b) < n; b++) {
		int cnt = 0;
		for (int j = 0; j < n; j += 1 << (b + 1)) {
			for (int k = 0; k < (1 << b); k++) {
				cnt += ai[j + k] < ai[j + (1 << b) + k];
			}
		}
		ans += min(cnt, n / 2 - cnt);
	}
	cout << min(inv, ans) << '\n';
}

int32_t main(){
#ifndef LOCAL
	cin.tie(0)->sync_with_stdio(false);
#endif
	int t = 1;
	// cin >> t;
	while (t--) {
		solve();
	}
}