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.

import java.io.IOException;
import java.io.InputStreamReader;
import java.io.BufferedReader;
import java.util.*;



import java.math.*;
import java.io.*;
import java.text.*;
import java.math.BigInteger;
public class Main {

	static class Interval {
		      int start;
		      int end;
		      Interval() { start = 0; end = 0; }
		      Interval(int s, int e) { start = s; end = e; }
		  }
	static class pair{
		int x;
		int y;
		public pair(int a,int b) {
			this.x=a;
			this.y=b;
		}
	}
	 public static boolean[] sieve(long n)
	    {
	        boolean[] prime = new boolean[(int)n+1];
	        Arrays.fill(prime,true);
	        prime[0] = false;
	        prime[1] = false;
	        long m = (long)Math.sqrt(n);
	        for(int i=2;i<=m;i++)
	        {
	            if(prime[i])
	            {
	                for(int k=i*i;k<=n;k+=i)
	                {
	                    prime[k] = false;
	                }
	            }
	        }
	        return prime;
	    } 
	 
	 //sorting
	
	 
	public static void sort(long arr[], int l, int r)
	    {
	        if (l < r)
	        {
	            // Find the middle point
	            int m = (l+r)/2;
	 
	            // Sort first and second halves
	            sort(arr, l, m);
	            sort(arr , m+1, r);
	 
	            // Merge the sorted halves
	            merge(arr, l, m, r);
	        }
	    }
	 
	 
	public static void merge(long arr[], int l, int m, int r)
	    {
	        // Find sizes of two subarrays to be merged
	        int n1 = m - l + 1;
	        int n2 = r - m;
	 
	        /* Create temp arrays */
	        long L[] = new long[n1];
	        long R[] = new long[n2];
	 
	        //Copy data to temp arrays
	        for (int i=0; i<n1; ++i)
	            L[i] = arr[l + i];
	        for (int j=0; j<n2; ++j)
	            R[j] = arr[m + 1+ j];
	 
	 
	        /* Merge the temp arrays */
	 
	        // Initial indexes of first and second subarrays
	        int i = 0, j = 0;
	 
	        // Initial index of merged subarry array
	        int k = l;
	        while (i < n1 && j < n2)
	        {
	            if (L[i] <= R[j])
	            {
	                arr[k] = L[i];
	                i++;
	            }
	            else
	            {
	                arr[k] = R[j];
	                j++;
	            }
	            k++;
	        }
	 
	        /* Copy remaining elements of L[] if any */
	        while (i < n1)
	        {
	            arr[k] = L[i];
	            i++;
	            k++;
	        }
	 
	        /* Copy remaining elements of R[] if any */
	        while (j < n2)
	        {
	            arr[k] = R[j];
	            j++;
	            k++;
	        }
	    }
	 
	 
	 public static boolean[] primeseive(long n) {
		 boolean prime[]=new boolean[(int)n+1];
		 
		 Arrays.fill(prime, true);
		 
		 prime[0]=false;
		 prime[1]=false;
		 
		 int m=(int) Math.sqrt(n);
		 
		 for(int i=2;i<=m;i++) {
			 if(prime[i]) {
				 
				 for(int k=i*i;k<=n;k+=i) {
					 prime[k]=false;
				 }
			 }
		 }
		 
		 return prime;
	 }
	 
	    
	    static long GCD(long a,long b)
	    {
	        if(b==0)
	        {
	            return a;
	        }
	        return GCD(b,a%b);
	    }
	 
	    
	    
	    static long gcdnik(long a,long b)
	    {
	        if(b==0)
	        {
	            return a;
	        }
	        return GCD(b,a%b);
	    }
	    
	    
	    static long CountCoPrimes(long n)
	    {
	        long res = n;
	        for(int i=2;i*i<=n;i++)
	        {
	            if(n%i==0)
	            {
	                while(n%i==0)
	                {
	                    n/=i;
	                }
	                res-=res/i;
	            }
	        }
	        if(n>1)
	        {
	            res-=res/n;
	        }
	        return res;
	    }
	 
	 
	    
	 
	    
	 
	    static boolean prime(int n)
	    {
	        for(int i=2;i*i<=n;i++)
	        {
	            if(i%2==0 ||i%3==0)
	            {
	                return false;
	            }
	        }
	        return true;
	    }
   static String userIdGeneration(String input1,String input2,int input3,int input4) {
	    	if(input1.length()==input2.length()) {
	    		String arr[]=new String[2];
	    		
	    		arr[0]=input1;
	    		arr[1]=input2;
	    		
	    		Arrays.sort(arr);
	    	char c=arr[0].charAt(0);
	    	   String output=c+arr[1];
	    		
	    	   String k=Integer.toString(input3);
	    	
	    	char d=k.charAt(input4-1);
	    	
	    	output+=d;
	    		
	    	char e=k.charAt(k.length()-input4);
	    	output+=e;
	    	String res="";
	    	for(int i=0;i<output.length();i++) {
	    		if(Character.isUpperCase(output.charAt(i))){
	    			res+=Character.toLowerCase(output.charAt(i));
	    		}
	    		else {
	    			res+=Character.toUpperCase(output.charAt(i));
	    		}
	      	}
	    	return res;
	    	}
	    	
	    	
	    	else  {
String arr[]=new String[2];
	    		arr[0]=input1.length()>input2.length()?input2:input1;
	    		arr[1]=input1.length()>input2.length()?input1:input2;
	    		
	    		char c=arr[0].charAt(0);
	    		
	    		String output=c+arr[1];
	    		
	    	String k=Integer.toString(input3);
	    	
	    	char d=k.charAt(input4-1);
	    	
	    	output+=d;
	    		
	    	char e=k.charAt(k.length()-input4);
	    	output+=e;
	    	String res="";
	    	for(int i=0;i<output.length();i++) {
	    		if(Character.isUpperCase(output.charAt(i))){
	    			res+=Character.toLowerCase(output.charAt(i));
	    		}
	    		else {
	    			res+=Character.toUpperCase(output.charAt(i));
	    		}
	    	}
	    return res;
	    	}
	    	
	    }
	static int length(int len) {
		
		if(len==1) {
			return 1;
		}
		else if(len==2) {
			return 3;
		}
		else if(len==3) {
			return 6;
		}
		else if(len==4) {
			return 10;
		}
		return 0;
	}
	
	
public static int LargestFour(int arr[]) {
	Arrays.sort(arr);

	int n=arr.length;
	int count=0;
	int sum=0;
	for(int i=n-1;i>=1;i--) {
		sum+=arr[i];
	
			count++;
			if(count==4) {
				break;
			
		}
		
	}
	
	if(count<4) {
		sum+=arr[0];
	}
	
	return sum;
}
//Nikunj Gupta
public static void insertionSort(int array[]) {  
    int n = array.length;  
    for (int j = 1; j < n; j++) {  
        int key = array[j];  
        int i = j-1;  
        while ( (i > -1) && ( array [i] > key ) ) {  
            array [i+1] = array [i];  
            i--;  
        }  
        array[i+1] = key;  
    }  
} 



  static String solve23(int n) {
int k=0;
while(true) {
	if(n-2020*k<0) {
		return "NO";
	}
	if((n-2020*k)%2021==0) {
		return "YES";
	}
	k++;
}
	  
	
	}
  public static String swapString(String a, int i, int j) {  
      char[] b =a.toCharArray();  
      char ch;  
      ch = b[i];  
      b[i] = b[j];  
      b[j] = ch;  
      return String.valueOf(b);  
  }  
	public static void permutation(String str,int start,int end,ArrayList<String> l,Set<String>set) {
		
		if(start==end-1) {
			set.add(str);
		}
		
		for(int i=start;i<end;i++) {
			str=swapString(str,start,i);
		
		permutation(str,start+1,end,l,set);
		
		swapString(str,start,i);
		
		}
		
		
		
	}


public static boolean solution(int j) {
	String str=Integer.toString(j);
	int zero=0;
	int one=0;
	for(int i=0;i<str.length();i++) {
		if(str.charAt(i)=='7') {
			one++;
		}else if(str.charAt(i)=='4') {
			zero++;
		}
	}
	
	
	if(one==zero) {
		return true;
	}
	
	
return false;
}
	
	
	


public static ArrayList<Interval> insert(ArrayList<Interval> intervals, Interval newInterval) {


ArrayList<Interval>ans=new ArrayList<Interval>();

int min=Math.min(newInterval.start,newInterval.end);
int max=Math.max(newInterval.end,newInterval.start);
int i=0;
boolean flag=false;
boolean place=false;

while(i<intervals.size()){
    int val1=newInterval.start;
    int val2=newInterval.end;
    
    
    if(min<=val1&&max>=val1&&max<=val2){
    Interval p2=	new Interval(min,val2);
    	ans.add(p2);
        
        place=true;
        
    }
    
    else if(min<val1&&max<val1){
        ans.add(new Interval(min,max));
        place=true; 
        ans.add(new Interval(val1,val2));
        i++;
        break;
       
    }
    else if(min>=val1&&max<=val2){
        ans.add(new Interval(val1,val2));
        place=true;
    }
    
    else if(min>val1&&min>val2){
        ans.add(new Interval(val1,val2));
    }
    else if(min>=val1&&max>val2){
        
         min=Math.min(min,val1);
  i++;
  while(i<intervals.size()){
      Interval na=intervals.get(i);
      
      if(max<=na.end&&max>=na.start){
          Interval ni=new Interval(val1,na.end);
      ans.add(ni);
      flag=true;
      place=true;
         // System.out.println("tes");
        break;
      }
      //System.out.println("tes"+"klkl");
      i++;
      
  }
    
        
        
        
    }
    
    
    
}


while(i<intervals.size()){
    Interval df=intervals.get(i);
    Interval g=new Interval(df.start,df.end);
    ans.add(g);
    
    i++;
}
  



    if(place==false){
     Interval ni=new Interval(min,max);
       //  System.out.println("tes");
       ans.add(ni); 
}

return ans;


  }


public static int lower_bound(ArrayList<Long> ar,long k)
{
    int s=0;
    int e=ar.size();
    while (s !=e)
    {
        int mid = s+e>>1;
        if (ar.get(mid) <k)
        {
            s=mid+1;
        }
        else
        {
            e=mid;
        }
    }
    if(s==ar.size())
    {
        return ar.size()-1;
    }
    return s;
}


	
		
		


        
	       
	       
	      
			
	
	
	
	
 


	


 
 
  
    
   
 private static void printsubsequences(String c, String st) {
	// TODO Auto-generated method stub
	
	 
	 if(c.length()==0) {
		 System.out.println(st);
		 return;
	 }
	 
	 
	 printsubsequences(c.substring(1),st+c.charAt(0));
	 printsubsequences(c.substring(1),st);
	 
	 
}

private static boolean compare(HashMap<Character, Integer> smap, HashMap<Character, Integer> pmap) {
		// TODO Auto-generated method stub
	 
	 for(char ch:smap.keySet()) {
		 if(smap.get(ch)!=pmap.get(ch)) {
			 return false;
		 }
	 }
		return true;
	}


private static boolean BinarySearch(int search, int[] val, int n)
 {
		// TODO Auto-generated method stub
		
	 int start=0;
	 int end=val.length-1;
	 while(start<=end) {
		 int mid=(start+end)/2;
		 
		 
		 if(val[mid]==search) {
			 return true;
		 }
		 else if(val[mid]<search) {
			 start=mid+1;
		 }
		 else {
			 end=mid-1;
		 }
		 
	 }
	 return false;
	 }


	
 
 
 
 static long findGCD(ArrayList<Long> arr,long start, long n) 
	    { 
	        long result = arr.get((int)start); 
	        for (int i = (int)start+1; i < n; i++) 
	            result = GCD(arr.get(i), result); 
	  
	        return result; 
	    } 
	 
	   
	 
	   

	    static long re(long n)
	    {
	        n+=1;
	        while(n%10==0)
	        {
	            n/=10;
	        }
	        return n;
	    }
	   
	   


	    
	 
	 
	 
	 
	 
	 
	    
	 
	    //xor range query
	    static long xor(long n)
	    {
	 
	        if(n%4==0)
	        {
	            return n;
	        }
	        if(n%4==1)
	        {
	            return  1;
	        }
	        if(n%4==2)
	        {
	            return n+1;
	        }
	        return 0;
	    }
	 
	    static long xor(long a,long b)
	    {
	        return xor(b)^xor(a-1);
	    }
	 
	 
	    
	 
	  
	   
	    
	 
	    
	       
	    
	 
	    
	   
	  
	 
	 

	   
	   
	    static void swap(char c,char p)
	    {
	        char t = c;
	        c = p;
	        p = t;
	    }
	 
	    static long max(long n,long m)
	    {
	        return Math.max(n,m);
	    }
	    static long min(long n,long m)
	    {
	        return Math.min(n,m);
	    }
	 
//	    double nd() throws IOException
//	    {
//	        return Double.parseDouble(in.next());
//	    }
//	    int ni() throws IOException
//	    {
//	        return Integer.parseInt(in.next());
//	    }
//	 
//	    long nl() throws IOException
//	    {
//	        return Long.parseLong(in.next());
//	    }
//	 
//	    String si() throws IOException
//	    {
//	        return in.next();
//	    }
//	 
//	 
	  
	   
	    static int abs(int n)
	    {
	        return Math.abs(n);
	    }
	 
	    static class Scanner 
	    {
	        StringTokenizer st;
	        BufferedReader br;
	 
	        public Scanner(InputStream s){  br = new BufferedReader(new InputStreamReader(s));}
	 
	        public String next() throws IOException 
	        {
	            while (st == null || !st.hasMoreTokens()) 
	            {
	                st = new StringTokenizer(br.readLine());
	            }
	            return st.nextToken();
	        }
	 
	        public int nextInt() throws IOException {return Integer.parseInt(next());}
	        
	        public long nextLong() throws IOException {return Long.parseLong(next());}
	 
	        public String nextLine() throws IOException {return br.readLine();}
	 
	        public boolean ready() throws IOException {return br.ready();}
	 
	 
	    }
	 
	    
public static char[] solve(char arr[]) {
	int i=0;
	
	char ans[]=new char[arr.length];
while(i<arr.length-1) {
	
		if(arr[i]=='B'&&arr[i+1]=='G') {
			ans[i]='G';
			ans[i+1]='B';
			i=i+2;
		}else {
			ans[i]=arr[i];
		i++;
		}
		
		
	}

if(i==arr.length-1) {
	ans[i]=arr[i];
}

	
	
	return ans;
	
}
public static void pairsort(ArrayList<pair>l){
	
	l.sort(new Comparator<pair>() {
		public int compare(pair o1,pair o2) {
			if(o1.x>o2.x) {
				return 1;
			}else {
				return -1;
			}
		}
	});

}

public static void main(String[] args) throws IOException{
  Scanner s=new Scanner(System.in);

  //long sum=s.nextLong();
 int n=s.nextInt();
 int arr[]=new int[n];
 
 
 for(int i=0;i<arr.length;i++) {
	 arr[i]=s.nextInt();
 }

int ans=Math.min(arr[0],arr[n-1]);

for(int i=0;i<n-1;i++) {
	ans=Math.min(ans,Math.max(arr[i],arr[i+1]));
}
System.out.println(ans);





}




	 
	 
	 
	class Pair implements Comparable<Pair>
	{
	   int x,y;
	    public Pair(int x,int y)
	    {
	        this.x = x;
	        this.y = y;
	    }
	    public int compareTo(Pair o)
	    {
	        return this.y-o.y;
	    }
	}
	
	}

