#include<bits/stdc++.h>
#define int long long
using namespace std;
const int N = 101;
const int inf = 0x3f3f3f3f;
int maimaimai;
int hqt = inf;
struct pei{
int angry;
int irascible;
};
pei zhuangjiao[11];
bool he[11];
void zhou(int lao , int mu , int ji){
if(ji > 0){
hqt = min(hqt , abs(lao - mu));
}
if(ji > maimaimai){
return;
}
for(int i = 1 ; i <= maimaimai ; i ++){
if(he[i]){
continue;
}	
he[i] = true;
zhou(lao * zhuangjiao[i].angry , mu + zhuangjiao[i].irascible , ji + 1);
he[i] = false;
}
}
signed main(){
freopen("stone.in" , "r" , stdin);
freopen("stone.out" , "w" , stdout);
cin >> maimaimai;
for(int i = 1 ; i <= maimaimai ; i ++){
cin >> zhuangjiao[i].angry >> zhuangjiao[i].irascible;
}
zhou(1 , 0 , 0);
cout << hqt;
return 0;
}