#include <bits/stdc++.h>
using namespace std;
#define int long long
const int MXN = 2e5 + 5, INF = 1e9 + 5;
int N;
int A[MXN], dp[MXN], pos[MXN];
struct fenwick_tree {
int n;
vector<int> tree;
fenwick_tree(int _n) {
n = _n;
tree.assign(n + 1, 0);
}
void increment(int pos, int val) {
for (int i = pos; i <= n; i += i & -i)
tree[i] += val;
}
int query(int pos) {
int res = 0;
for (int i = pos; i > 0; i -= i & -i)
res += tree[i];
return res;
}
};
signed main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
cin >> N;
for (int i = 1; i <= N; i++) {
cin >> A[i];
dp[i] = INF;
}
for (int i = 1; i <= N; i++) {
// Consider an array of all A[i] <= i, maintain relative positions only - compress
for (int j = 1, cur_pos = 1; j <= N; j++) {
if (A[j] <= i)
pos[A[j]] = cur_pos++;
}
fenwick_tree ft(N + 1);
int cost = 0;
for (int j = i; j >= 1; j--) {
int loc = pos[j] - ft.query(pos[j]);
cost += i - loc - 2 * ft.query(pos[j] - 1);
ft.increment(pos[j], 1);
dp[i] = min(dp[i], dp[j - 1] + cost);
}
}
cout << dp[N];
}
