# include <bits/stdc++.h>
using namespace std;
int a[100],b[100];
int ans=99999999;
int n;
void dfs(int i,int x,int y)
{
if(i>n)
{
if(x==1&&y==0)
{
return ;
}
ans=min(abs(x-y),ans);
return ;
}
dfs(i+1,x*a[i],y+b[i]);//选择这种材料;
dfs(i+1,x,y);//不选择这种材料
}
int main()
{
cin>>n;
for(int i=1;i<=n;i++)
{
scanf("%d%d",&a[i],&b[i]);
}
dfs(1,1,0);
cout<<ans;
}