#!/bin/python

import sys
n = int(raw_input().strip())
m = map(int, raw_input().strip().split(' '))
# your code goes here
count = 0 
for i in range(1,n):
    if m[i] >= m[i-1]:
        count += 1
        pass
    else:
        break
    pass

ac = 1
for i in range(0,count):
    ac *= 2
    ac %=10e9+7
    pass

print int(ac)