/* IMPORTANT: class must not be public. */
import java.util.*;
/*
 * uncomment this if you want to read input.
import java.io.BufferedReader;
import java.io.InputStreamReader;
*/

class TestClass {


    public  static boolean checkSorted(int arr[])
    {
        if(arr.length==1)
        {
            return true;
        }
        int newArr[]=new int[arr.length-1];
        for(int i=1;i<arr.length;i++)
        {
            newArr[i-1]=arr[i];
        }

        boolean ans= checkSorted(newArr);
        if(!ans)
        {
            return false;
        }

        if(arr[0]<=arr[1])
        {
            return true;
        }
        else
        {
            return false;
        }
    }
    public static void main(String args[] ) throws Exception {
        int size;
        Scanner sc=new Scanner(System.in);
        size=sc.nextInt();
        int arr[]=new int[size];
        for(int i=0;i<size;i++)
        {
            arr[i]=sc.nextInt();
        }

    System.out.println(checkSorted(arr));
    }
}