#!/usr/bin/env ruby

a = STDIN.gets
a = a.chomp
b = a.to_i
c= STDIN.gets
array1 = Array.new(b)
i=0


strAry = c.split()
strAry.each do |youso|
  array1[i]=youso
i=i+1
end
i=0
j=0
k=0
while i<b-1 
	j=i+1

	while j<b

	if array1[i].to_i==j+1 && array1[j].to_i==i+1 
	k=k+1	
	end
	j=j+1
	end
i=i+1
end

if k%2==0
puts("Yes")
end
if k%2==1
puts("No")
end