#include <bits/stdc++.h>
using namespace std;
#define ll long long
struct node{
	ll a,b;
}x[200005];
bool cmp(node A,node B){
	return A.a+2*A.b>B.a+2*B.b;
}
int main(){
	ll n,sum=0,cnt=0,ans=0;
	cin>>n;
	for(ll i=0;i<n;i++){
		cin>>x[i].a>>x[i].b;
		sum+=x[i].a;
	}
	sort(x,x+n,cmp);
	ll i=0;
	while(ans<=sum){
		cnt++;
		ans+=x[i].a+x[i].b;
		sum-=x[i].a;
		i++;
	}
	cout<<cnt<<'\n';
	return 0;
}