n,m=gets.split(" ").map{|e| e.to_i}
arr=[]
n.times{
	t1,t2=gets.split(" ").map{|e| e.to_i}
	arr<<t1-t2
}
arr.sort!
l1=0
r1=n-1
while l1<r1
	t=arr[r1]-arr[l1]
	if t<0 then
		arr[l1]-=t
		r1-=1
	elsif t==0
		r1-=1
	else
		arr[r1]=t
		l1+=1
	end
	p [t,l1,r1]
end
if m<=l1 then
	puts "Yes"
else
	puts "No"
end