#include <bits/stdc++.h>
using namespace std;
#define F first
#define S second
#define FOR(i,a,b) for (auto i = (a); i <= (b); ++i)
#define NFOR(i,a,b) for(auto i = (a); i >= (b); --i)
#define all(x) (x).begin(), (x).end()
#define sz(x) int(x.size())
#define mp(i,a) make_pair(i,a)
#define pb(a) push_back(a)
#define bit(x,b) (x&(1LL<<b))
typedef long long int lli;
typedef pair <lli,lli> ii;
typedef pair <lli,ii> iii;
typedef vector <lli> vi;
set<int> arr[1000001];
int arr1[1000001],ch[1000001]={},c=0;
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
int test=1,co=0;
for(;test>0;--test)
{
int n;
cin>>n;
for(int i=0;i<n;++i)
{
cin>>arr1[i];
arr[arr1[i]].insert(i);
}
for(int i=0;i<n;++i)
{
if(ch[i]==0)
{
c++;
int cur=arr1[i],in=i;
ch[i]=1;
arr[cur].erase(arr[cur].begin());
while(cur!=1)
{
co++;
auto it=arr[cur-1].lower_bound(in);
if(it==arr[cur-1].end())
break;
else
{
in=(*it);
cur--;
ch[in]=1;
arr[cur].erase(it);
}
}
}
}
cout<<c<<endl;
}
return(0);
}
