n,k=gets.split.map{|e| e.to_i}
x=gets.split.map{|e| e.to_i-1}
hs={}
i=0
while x.empty? == false
	e=x.shift
	#p [e,i,k,hs]
	if e==i
		i+=1
		next
	end
	
	if hs.key?(i)!=false
		i+=1
		next
	end
	hs[e]=0
	k-=1
	i+=1
end
if k<0
	puts "YES"
elsif k%2==0
	puts "YES"
else
	puts "NO"
end