#include <bits/stdc++.h>
//#include <ext/pb_ds/detail/standard_policies.hpp>
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
//#pragma GCC optimize("Ofast")
//#pragma GCC target("avx2")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4")
using namespace std;
//using namespace __gnu_pbds;
//template <typename T> using ordered_set = tree <T, null_type, less < T >, rb_tree_tag, tree_order_statistics_node_update>;
mt19937 gen(time(0));
#define ll long long
#define ld long double
#define pb push_back
#define F first
#define S second
#define TIME clock() * 1.0 / CLOCKS_PER_SEC
#define sz(a) int32_t(a.size())
#define endl '\n'
//#define int long long
const int N = 5e5 + 100;
const int M = 31;
const int mod = 1e9 + 7;
const ll inf = 1e18 + 7;
int dp[N], a[N];
int32_t main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
#ifdef LOCAL
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#else
// freopen("input.txt", "r", stdin);
// freopen("output.txt", "w", stdout);
#endif // LOCAL
int n;
cin >> n;
for(int i = 0; i < n; i++)
cin >> a[i];
for(int i = 0; i < n; i++)
{
dp[i] = i + 1;
if (i) dp[i] = min(dp[i], dp[i - 1] + 1);
for(int j = i - 1; j >= 0; j--)
{
if (a[j] > a[j + 1]) break;
int fl = 0;
for(int z = 0; z < j; z++)
{
if (a[z] > a[j] && a[z] < a[i])
{
fl = 1;
break;
}
}
if (!fl) dp[i] = min(dp[i], (j ? dp[j - 1] : 0) + 1);
}
}
cout << dp[n - 1];
}
