#include <algorithm>
#include <climits>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <ctime>
#include <iostream>
#include <sstream>
#include <functional>
#include <map>
#include <string>
#include <cstring>
#include <vector>
#include <queue>
#include <stack>
#include <deque>
#include <set>
#include <list>
#include <numeric>
using namespace std;
const double PI = 3.14159265358979323846;
const double EPS = 1e-12;
typedef pair<int,int> P;
typedef long long ll;
typedef unsigned long long ull;
const ll INF = 1LL<<60;
#define N 1000
ll a[N], b[N];
ll n;
ll f(ll x){
	ll mn = 1e18, mx = 0;
	for(int i = 0; i < n; i++){
		ll r = a[i] + b[i]*x;
		mn = min(mn, r);
		mx = max(mx, r);
	}
	return mx-mn;
}
int main(){
	cin>>n;
	for(int i = 0; i < n; i++) cin>>a[i]>>b[i];
	ll lb = 1, ub = 1e9+100; // [lb, ub)
	while(ub-lb>10){
		ll lb2 = (lb*2+ub)/3, ub2 = (lb+ub*2)/3;
		ll lv = f(lb2), rv = f(ub2);
		if(lv<=rv) ub = ub2;
		else lb = lb2;
	}
	ll res = lb, val = f(res);
	for(ll i = lb+1; i < ub; i++){
		ll v = f(i);
		if(val>v){
			res = i;
			val = v;
		}
	}
	cout<<res<<endl;
	return 0;
}