def 🎍(a,b,c)
    a != c && ((a < b && b > c) || (a > b && b < c))
end

n = gets.to_i
arr = gets.split.map(&:to_i)

ok = false
(0...n).to_a.combination(2) do |i, j|
    arr[i], arr[j] = arr[j], arr[i]
    ok ||= arr.each_cons(3).all?{|a| 🎍(*a)}
    arr[i], arr[j] = arr[j], arr[i]
end

puts ok ? 'Yes' : 'No'