def f(t,l,r,arr)
	p [l,r]
	if l==r then
		return l
	end
	m=(l+r)/2
	t3=arr[m]-t
	p [m,t,t3]
	if t3<=0 then
		return f(t,l,m,arr)
	else
		return f(t,m+1,r,arr)
	end
end
n,p,q=gets.split(" ").map{|e| e.to_i}
t=Rational(p, q+p)
tA=[0]
tB=[0]
tAB=[0]
n.times{|i|
	a,b=gets.split(" ").map{|e| e.to_i}
	tA<<tA[i]+a
	tB<<tB[i]+b
	tAB<<tAB[i]+a+b
}
arr=[]
(1..n).each{|i|
	arr<<Rational(tA[i],tAB[i])
}
arr<<Rational(-1,1)
arr<<Rational(10**18,1)
arr=arr.sort.reverse
 
n.times{|i|
	t2=t
	if i>0 then
		t2+=Rational(tA[i],tAB[i])
	end
	p f(t2,0,n+1,arr)
}

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

NSAxIDMKMyA5CjEgMgo0IDYKMSA1CjUgMw==

5 1 3
3 9
1 2
4 6
1 5
5 3