#include<bits/stdc++.h>
using namespace std;
int n;
int minn=0x7f; 
int a[15],b[15];
void dfs(int k,int s1,int s2){
	if(k==n){
		if(s1==1&&s2==0){
			return;
		}
		minn=min(abs(s1-s2),minn);
		return;
	}
	
	dfs(k+1,s1*a[k],s2+b[k]);
	dfs(k+1,s1,s2);
}
int main(){
	ios::sync_with_stdio(false);
	cin>>n;
	for(int i=0;i<n;i++){
		cin>>a[i]>>b[i];
	}
	dfs(0,1,0);
	cout<<minn;
	return 0;
}