#include<cstdio>
#include<vector>
#include<algorithm>
#include<climits>
using namespace std;
typedef long long ll;
ll N;
ll a[1000],b[1000];
ll f(ll x){
    ll mi=LLONG_MAX,ma=0;
    for(int i=0;i<N;i++){
        ll val=a[i]+b[i]*x;
        mi=min(mi,val);
        ma=max(ma,val);
    }
    return ma-mi;
}
int main(){
    scanf("%lld",&N);
    for(int i=0;i<N;i++)scanf("%lld%lld",&a[i],&b[i]);

    ll l=0,r=1e9+10;
    for(int i=0;r-l>100ll;i++){
        ll p1=(l*2+r)/3,p2=(l+r*2)/3;
        if(f(p1)<=f(p2))r=p2;
        else l=p1;
    }
    ll mi=LLONG_MAX,miv;
    for(ll i=l;i<=r;i++){
        if(mi>f(i)){
            mi=f(i);
            miv=i;
        }
    }
    printf("%lld\n",miv);
}