// Source: https://usaco.guide/general/io

#include <bits/stdc++.h>
using namespace std;
#define int long long

struct evszam{
	int ev,ho,nap;
};


vector<int> hok {31,28,31,30,31,30,31,31,30,31,30,31};

int atvalt(evszam a){
	int cnt=0;
	for(int i = 1950;i<a.ev;i++){
		cnt+=365;
		if(i%4==0)cnt++;
	}
	for(int i = 0;i<a.ho;i++){
		cnt+=hok[i];
	}
	if(a.ho>2&&a.ev%4==0)cnt++;
	return cnt+a.nap;
}

signed main(){
	int n;cin>>n;
	vector<int> v(n);
	for(int i = 0;i<n;i++){
		cin>>v[i];
	}
	sort(v.rbegin(),v.rend());
	int ans=0;
	for(int i = 0;i<n;i++){
		ans=max(ans,v[i]+i);
	}cout<<ans<<endl;
}