#include <bits/stdc++.h>
 
using namespace std;
 
int check(vector<int>&a, int n, int size){
    int cnt=0;
    int mx =-1;
    for(int i=0;i<n;i++){
        if(a[i]>=size) cnt++;
        else cnt=0;
 
        mx=max(mx, cnt);
    }
    return mx>=size;
}
 
int main()
{
    int n; cin>>n;
 
    vector<int>a(n);
    for(int &i:a) cin>>i;
 
    int lo = 1;
    int hi = 1e9;
    int ans = -1;
 
    while(lo<=hi){
        int mid = lo + (hi-lo)/2;
 
        if(check(a, n, mid)){
            ans = mid;
            lo = mid + 1;
        }else{
            hi = mid - 1;
        }
    }
 
    cout<<ans<<endl;
 
    return 0;
}

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