#include<bits/stdc++.h>
#define int long long
#define pb push_back
#define double long double
using namespace std;
const int mod = 1e9 + 7;
const int N = 2e5 + 5;
struct SEGT{
vector<int> tree;
void init(int n){
tree.assign(4*n, 0);
}
void update(int ind, int l, int r, int pos, int val){
if(l == r) tree[ind] = val;
else{
int m = (l + r)/2;
if(pos <= m) update(ind*2, l, m, pos, val);
else update(ind*2+1, m+1, r, pos, val);
tree[ind] = tree[ind*2] + tree[ind*2+1];
}
}
int query(int ind, int l, int r, int ql, int qr){
if(l > r || l > qr || r < ql) return 0;
if(l >= ql && r <= qr) return tree[ind];
else{
int m = (l + r)/2;
return query(ind*2, l, m, ql, qr) + query(ind*2+1, m+1, r, ql, qr);
}
}
int sum(int l, int r){
return query(1LL, 1LL, tree.size()/4, l, r);
}
};
int32_t main(){
ios_base::sync_with_stdio(false), cin.tie(0), cout.tie(0);
// dp[we put first i elements without changing order of other ones] = minimum cost to get this array
int n;
cin>>n;
vector<int> a(n), dp(n+1, mod);
for(int i = 0; i < n; i++){
cin>>a[i];
}
vector<int> arr[n+1];
for(int i = 0; i < n; i++){
for(int j = 1; j <= a[i]; j++){
arr[j].pb(a[i]);
}
}
vector<vector<int> > cost(n+1, vector<int>(n+1, mod));
dp[0] = 0;
/*
for(int i = 1; i <= n; i++){
for(int pre = i-1; pre >= 0; pre--){
int cst = 0, ind = 0;
vector<int> sim = arr[pre + 1];
for(int j = i; j >= pre + 1; j--){
int possim = 0;
for(int pos = 0; pos < sim.size(); pos++){
if(sim[pos] == j){
possim = pos;
break;
}
}
cst += possim - ind;
for(int pos = possim; pos >= ind + 1; pos--) sim[pos] = sim[pos - 1];
sim[ind] = j;
ind++;
}
cost[pre][i] = cst;
}
}
*/
vector<int> presm(n+1), ind(n+1);
for(int arri = 1; arri <= n; arri++){
for(int j = 0; j <= n; j++) presm[j] = 0;
int m = arr[arri].size();
SEGT seg;
seg.init(n+1);
for(int i = m-1; i >= 0; i--){
int val = arr[arri][i];
presm[val] = seg.sum(1, val - 1);
ind[val] = i;
seg.update(1, 1, n+1, val, 1);
}
int cnt = 0;
for(int j = arri; j <= n; j++){
cnt += (ind[j] - presm[j]);
cost[arri - 1][j] = cnt;
}
}
for(int i = 1; i <= n; i++){
for(int pre = i-1; pre >= 0; pre--){
dp[i] = min(dp[i], dp[pre] + cost[pre][i]);
}
}
cout<<dp[n]<<endl;
return 0;
}
