import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution {
    public static long pow(long n, long p, long m) {
		long result = 1;
		if (p == 0)
			return 1;
		if (p == 1)
			return n;
		while (p != 0) {
			if (p % 2 == 1)
				result *= n;
			if (result >= m)
				result %= m;
			p >>= 1;
			n *= n;
			if (n >= m)
				n %= m;
		}
		return result;
	}

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int n = in.nextInt();
        int mod = (int) 1e9+7;
        int[] m = new int[n];
        for(int m_i=0; m_i < n; m_i++){
            m[m_i] = in.nextInt();
        }
        int prev = m[0];
        boolean rflag = true;
        boolean fflag = true;    
        for(int m_i=1; m_i < n; m_i++){
            rflag = rflag&&(prev > m[m_i]);
            fflag = fflag&&(prev < m[m_i]);
            prev = m[m_i];
        }
        long ans=0;
       if(fflag){ 
          while(n>0){
             ans+=pow(2,n-1,mod);
             ans%=mod;
             n-=3;
         }
       }
        if(rflag) ans=1;
        
        System.out.println(ans);
        
        
        // your code goes here
    }
}