#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef vector<int> VI;
typedef vector<VI> VVI;
#define REP(i, n)           for(int(i)=0;(i)<(n);++(i))
#define FOR(i, f, t)        for(int(i)=(f);(i)<(t);(++i))
#define RREP(i, n)          for(int(i)=(n)-1;(i)>=0;--(i))
const int MOD = int(1e9+7);


ll a[1111],b[1111];
int N;

int main(){
    do { cin.tie(0); ios_base::sync_with_stdio(false); } while(0);
    cin >> N;
    REP(i,N) cin >> a[i] >> b[i];

    auto f = [](ll x)->ll{
        ll minv = 1LL<<61, maxv = 0;
        REP(i,N){
            ll l = a[i] + b[i]*x;
            minv = min(minv, l);
            maxv = max(maxv, l);
        }
        return maxv-minv;
    };
    ll l = 1, r = INT_MAX;
    while(l<r && (r-l) > 3){
        ll l2 = l+(r-l)/3;
        ll r2 = r-(r-l)/3;
        ll suml = f(l2);
        ll sumr = f(r2);
        if(sumr < suml){
            l = l2;
        } else {
            r = r2;
        }
    }
    ll minv = 1LL<<61, res = 1;
    for(ll c = l; c <= r; c++){
        ll v = f(c);
        if(minv > v){
            minv = v;
            res = c;
        }
    }

    cout << res << endl;
    return 0;
}