#include <bits/stdc++.h>
#define sz(x) ((int)x.size())
#define PB push_back
#define all(x) x.begin(),x.end()
using namespace std;
const int N = (1 << 20);
const int oo = 2e9;
int a[N], n, f[N], kol[N], pref[N], vl, sg[2 * N];
vector<int> vc;
set<int> st;
set<int>::iterator IT;
bool ok(int l, int r){
int kl = pref[r] - pref[l];
if (kl > 0) return 0;
return (a[r] <= vl);
}
int Min(int l, int r){
l += N; r += N;
int res = oo;
while (l <= r){
res = min(res, sg[l]);
res = min(res, sg[r]);
l = (l + 1) >> 1;
r = (r - 1) >> 1;
}
return res;
}
void update(int ps){
ps += N;
sg[ps] = f[ps - N];
ps >>= 1;
for (; ps > 0; ps >>= 1)
sg[ps] = min(sg[ps + ps + 1], sg[ps + ps]);
}
int main(){
ios_base::sync_with_stdio(0); cin.tie(0);
// freopen("in.txt","r",stdin);
cin >> n;
for (int i = 0; i < n; i++) {
cin >> a[i];
st.insert(a[i]);
kol[a[i]]++;
}
pref[0] = 0;
for (int i = 1; i < n; i++)
pref[i] = pref[i - 1] + bool(a[i] < a[i - 1]);
f[n] = 0;
for (int it = n - 1; it >= 0; it--){
kol[a[it]]--;
if (kol[a[it]] == 0)
st.erase(a[it]);
vl = oo;
if (sz(st)){
IT = st.upper_bound(a[it]);
if (IT != st.end())
vl = *IT;
}
int l = it, r = n - 1;
while (l < r){
int md = (l + r + 1) >> 1;
if (ok(l, md))
l = md;
else r = md - 1;
}
f[it] = Min(it + 1, l + 1) + 1;
update(it);
}
cout << f[0];
return 0;
}
