#include <iostream>
#include <cstdio>
#include <set>
#include <vector>
#include <algorithm>
using namespace std;
typedef long long ll;
#define rep(i,n) for(int i=0;i<(n);i++)
#define reps(i,f,n) for(int i=(f);i<(n);i++)
const ll INF = 1LL << 60;

ll n;
ll a[1010], b[1010];

ll search(ll m){
	ll ma = 0, mi = INF;
	rep(i, n){
		ll num = a[i] + b[i] * m;
		ma = max(ma, num);
		mi = min(mi, num);
	}
	return ma - mi;
}

int main(void){
	cin >> n;
	bool flag = true;
	rep(i, n){
		cin >> a[i] >> b[i];
		if(!(a[i] == 0 && b[i] == 0)) flag = false;
	}
	if(flag){
		printf("1\n"); return 0;
	}

	//下とつ
	ll l = 1, r = 1000000001;
	for (int i = 0; i < 50; ++i){
		ll m1 = (l * 2 + r) / 3;
		ll m2 = (l + r * 2) / 3;
		if(search(m1) > search(m2)){//左側が高い
			l = m1;
		}else{//右側が高い
			r = m2;
		}
	}

	ll ans = l, minn = INF;
	// printf("k %d %d\n", l, r);
	for (int i = l; i <= r; ++i){
		ll t = search(i);
		if(minn > t){
			minn = t;
			ans = i;
		}
	}
	printf("%lld\n", ans);
	return 0;
}