#include "bits/stdc++.h"
using namespace std;

#define int long long
#define REP(i, n) for(int i=0; i<(n); i++)
#define FOR(i, a, b) for(int i=(a);i<(b);i++)
#define MAX 1e15

int N,T;
vector<int> A, B;
int calc(int x) {
    int ret = 0;
    int maxc = 0;
    int minc = MAX;
    REP(i,N) {
        int c = A[i] + B[i] * x;
        maxc = max(maxc, c);
        minc = min(minc, c);
    }
    return maxc - minc;
}
signed main()
{
    cin >> N;
    A.resize(N);
    B.resize(N);
    REP(i,N) cin >> A[i] >> B[i];
    int high = MAX;
    int low = 1;
    while(high - low > 5) {
        int m1 = low + (high - low) / 3;
        int m2 = low + (high - low) * 2 / 3;
        int c1 = calc(m1);
        int c2 = calc(m2);
        if (c1 <= c2) {
            high = m2;
        } else {
            low = m1;
        }
    }
    int minc = MAX;
    int ans = -1;
    FOR(k,low,high) {
        int c = calc(k);
        if (c < minc) {
            ans = k;
            minc = c;
        }
    }
    cout << ans << endl;
    return 0;
}