#include<iostream>
#include<algorithm>
#include<cmath>
#include<cstdio>
using namespace std;
long long n,i,a[50001],max1,x,d=1,q; 
int main () {
cin>>n;
for (i=1;i<=n;i++)
{
cin>>a[i];
}
for (i=1;i<=n;i++)
{
if (a[i]==a[i-1]+1 && d==1) {d++; x=a[i-1];}
if (a[i]==a[i-1]+1 && d>1)  d++;
if (a[i]!=a[i-1]+1)
{
if (d>max1) {max1=d; q=x; d=1; x=0;}
}
}
cout<<q<<endl;
return 0;
}
