In Berland the opposition is going to arrange mass walking on the boulevard. The boulevard consists of n tiles that are lain in a row and are numbered from 1 to n from right to left. The opposition should start walking on the tile number 1 and the finish on the tile number n. During the walk it is allowed to move from right to left between adjacent tiles in a row, and jump over a tile. More formally, if you are standing on the tile number i (i < n - 1), you can reach the tiles number i + 1 or the tile number i + 2 from it (if you stand on the tile number n - 1, you can only reach tile number n). We can assume that all the opposition movements occur instantaneously.

In order to thwart an opposition rally, the Berland bloody regime organized the rain. The tiles on the boulevard are of poor quality and they are rapidly destroyed in the rain. We know that the i-th tile is destroyed after ai days of rain (on day ai tile isn't destroyed yet, and on day ai + 1 it is already destroyed). Of course, no one is allowed to walk on the destroyed tiles! So the walk of the opposition is considered thwarted, if either the tile number 1 is broken, or the tile number n is broken, or it is impossible to reach the tile number n from the tile number 1 if we can walk on undestroyed tiles.

The opposition wants to gather more supporters for their walk. Therefore, the more time they have to pack, the better. Help the opposition to calculate how much time they still have and tell us for how many days the walk from the tile number 1 to the tile number n will be possible.

Input

The first line contains integer n (1 ≤ n ≤ 103) — the boulevard's length in tiles.

The second line contains n space-separated integers ai — the number of days after which the i-th tile gets destroyed (1 ≤ ai ≤ 103). 

Output

Print a single number — the sought number of days.

Examples

Input

4
10 3 5 10


Output

5


Input

5
10 2 8 3 5


Output

5

Note

In the first sample the second tile gets destroyed after day three, and the only path left is 1 → 3 → 4. After day five there is a two-tile gap between the first and the last tile, you can't jump over it.

In the second sample path 1 → 3 → 5 is available up to day five, inclusive. On day six the last tile is destroyed and the walk is thwarted.
/*
 ~/BAU/ACM-ICPC/Teams/Rampage/MMZA
 ~/sudo apt-get verdict Accepted
 practice...
*/
//package javaapplication1;

//import java.util.Scanner;


import java.io.BufferedReader;
import java.io.DataInputStream;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.io.UnsupportedEncodingException;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.util.*;

public class Main {
    static final int Mod=(int)1e9+7;
    static final int N=(int)2e5+5;
    static int n,m,dx[]={0,0,-1,1},dy[]={-1,1,0,0};
    static char grid[][]=new char[55][55];
    static boolean vis[][]=new boolean[55][55];
    static pair parent[][]=new pair[55][55];
    public static void main(String[] args) throws IOException {
       // Reader.init(System.in);
        //Scanner in=new Scanner(new FileInputStream("input.txt"));
        FastReader in=new FastReader();
        //in=new FileReader("input.txt");
        //PrintWriter out=new PrintWriter(new FileOutputStream("output.txt"));
        PrintWriter out=new PrintWriter(System.out);           
        Main ob=new Main();
        int n=in.nextInt(),arr[]=new int [n+1],dd=0;
        for(int i=0;i<n;i++)
            arr[i]=in.nextInt();
        /*if(n==1){
            out.println(arr[0]);
            out.close();
            return;
        }*/
        boolean cont=true;
        while(cont){
            if(arr[0]<=dd)
                break;
            for(int i=0;i<n-1;){
                if(i+2<n&&arr[i+2]>dd){
                    i+=2;
                }
                else if(i+1<n&&arr[i+1]>dd){
                    i++;
                }
                else{
                    cont=false;
                    break;
                }
            }
            if(cont)
            dd++;
        }
        out.println(dd);
        
        
        out.close();
    }
    static int[] reverse(int [] arr){
        ArrayList<Integer> temp=new ArrayList();
        for(int i=0;i<arr.length;i++)
            temp.add(arr[i]);
        Collections.reverse(temp);
        for(int i=0;i<temp.size();i++)
            arr[i]=temp.get(i);
        return arr;
    }
    static String reverse(String s){
        String temp="";
        for(int i=s.length()-1;i>=0;i--)
            temp+=s.charAt(i);
        return temp;
    }
    static String sort(String inputString) 
    { 
        ArrayList<Character> arr=new ArrayList();
        for(int i=0;i<inputString.length();i++)
            arr.add(inputString.charAt(i));
        Collections.sort(arr);
        StringBuilder sb=new StringBuilder();
        for(int i=0;i<arr.size();i++)
            sb.append(arr.get(i));
        
        return sb.toString(); 
    } 
     
    static boolean next_permutation(int[] p, int len) {
        int a = len - 2;
        while (a >= 0 && p[a] >= p[a + 1]) {
            a--;
        }

        if (a == -1) {
            return false;
        }

        int b = len - 1;
        while (p[b] <= p[a]) {
            b--;
        }

        p[a] += p[b];
        p[b] = p[a] - p[b];
        p[a] -= p[b];

        for (int i = a + 1, j = len - 1; i < j; i++, j--) {
            p[i] += p[j];
            p[j] = p[i] - p[j];
            p[i] -= p[j];
        }

        return true;
    }
    static int lower_bound(ArrayList<Integer> arr,int key) {
        int len = arr.size();
        int lo = 0;
        int hi = len-1;
        int mid = (lo + hi)/2;
        while (true) {
            int cmp = (arr.get(mid)==key?1:0);
            if (cmp == 0 || cmp > 0) {
                hi = mid-1;
                if (hi < lo)
                    return mid;
            } else {
                lo = mid+1;
                if (hi < lo)
                    return mid<len-1?mid+1:-1;
            }
            mid = (lo + hi)/2;
        }
    }
    static int upper_bound(ArrayList<Integer> arr, int key) {
        int len = arr.size();
        int lo = 0;
        int hi = len-1;
        int mid = (lo + hi)/2;
        while (true) {
            int cmp = (arr.get(mid)==key?1:0);
            if (cmp == 0 || cmp < 0) {
                lo = mid+1;
                if (hi < lo)
                    return mid<len-1?mid+1:-1;
            } else {
                hi = mid-1;
                if (hi < lo)
                    return mid;
            }
            mid = (lo + hi)/2;
        }
    }
    static int gcd(int a,int b){
        return b==0?a:gcd(b,a%b);
    } 
    static double dot(Point p,Point q){
        return (p.x*q.x+p.y*q.y);
    }
    static double cross(Point p,Point q){
        return (p.x*q.y-p.y*q.x);
    }
    static Point computeLineIntersection(Point a,Point b,Point c,Point d){
        b=b.sub(a);d=c.sub(d);c=c.sub(a);
        return a.add(b.mulCon(cross(c,d)).devideCon(cross(b,d)));
    }
   static class FastReader 
        { 
        BufferedReader br; 
        StringTokenizer st; 
  
        public FastReader() 
        { 
            br = new BufferedReader(new
                     InputStreamReader(System.in)); 
        } 
  
        String next() 
        { 
            while (st == null || !st.hasMoreElements()) 
            { 
                try
                { 
                    st = new StringTokenizer(br.readLine()); 
                } 
                catch (IOException  e) 
                { 
                    e.printStackTrace(); 
                } 
            } 
            return st.nextToken(); 
        } 
  
        int nextInt() 
        { 
            return Integer.parseInt(next()); 
        } 
  
        long nextLong() 
        { 
            return Long.parseLong(next()); 
        } 
  
        double nextDouble() 
        { 
            return Double.parseDouble(next()); 
        } 
  
        String nextLine() 
        { 
            String str = ""; 
            try
            { 
                str = br.readLine(); 
            } 
            catch (IOException e) 
            { 
                e.printStackTrace(); 
            } 
            return str; 
        } 
    } 
  
}
class Reader {

    static BufferedReader reader;
    static StringTokenizer tokenizer;

    static void init(InputStream input) throws UnsupportedEncodingException {
        reader = new BufferedReader(
                new InputStreamReader(input, "UTF-8"));
        tokenizer = new StringTokenizer("");
    }

    static void init(String url) throws FileNotFoundException {
        reader = new BufferedReader(new FileReader(url));
        tokenizer = new StringTokenizer("");
    }

    static String next() throws IOException {
        while (!tokenizer.hasMoreTokens()) {
            //TODO add check for eof if necessary
            tokenizer = new StringTokenizer(
                    reader.readLine());
        }
        return tokenizer.nextToken();
    }

    static String nextLine() throws IOException {
        return reader.readLine();
    }

    static int nextInt() throws IOException {
        return Integer.parseInt(next());
    }

    static double nextDouble() throws IOException {
        return Double.parseDouble(next());
    }

    static long nextLong() throws IOException {
        return Long.parseLong(next());
    }
}
class Point{    
    double x,y;
    Point(double _x,double _y){
        x=_x;
        y=_y;
    }
    Point add(final Point p){
        return new Point(x+p.x,y+p.y);
    }
    Point sub(final Point p){
        return new Point(x-p.x,y-p.y);
    }
    Point mulCon(final double c){
        return new Point(c*x,c*y);
    }
    Point devideCon(final double c){
        return new Point(x/c,y/c);
    }
}
class  pair implements Comparator<pair>{
    int first,second;
    pair(){}
    pair(int a,int b){
        first = a;
        second = b;
    }
   /* pair(pair a,pair b){
        first = a;
        second = b;
    }*/
    @Override 
    public int compare(pair a,pair b){
        return (a.first-b.first);
    }
}
