/* package whatever; // don't place package name! */

import java.util.*;
import java.lang.*;
import java.io.*;

/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static int sol(int arr[],int k){
		int n=arr.length;
		int count=Integer.MAX_VALUE;
		Map<Integer,Integer>mp=new HashMap<>();
		for(int i=n-1;i>=0;i--){
			if(mp.containsKey(k-arr[i])){
				int idx=mp.get(k-arr[i]);
				count=Math.min(count,idx-i+1);
			}
			mp.put(arr[i],i);
		}
		return count;
	}
	public static void main (String[] args) throws java.lang.Exception
	{
		// your code goes here
		Scanner sc=new Scanner(System.in);
		int n=sc.nextInt();
		
		int arr[]=new int[n];
		for(int i=0;i<n;i++) arr[i]=sc.nextInt();
		
		int target=sc.nextInt();
		
		System.out.println(sol(arr,target));
	}
}