#include <bits/stdc++.h>
using namespace std;
typedef signed long long ll;

#undef _P
#define _P(...) (void)printf(__VA_ARGS__)
#define FOR(x,to) for(x=0;x<(to);x++)
#define FORR(x,arr) for(auto& x:arr)
#define ITR(x,c) for(__typeof(c.begin()) x=c.begin();x!=c.end();x++)
#define ALL(a) (a.begin()),(a.end())
#define ZERO(a) memset(a,0,sizeof(a))
#define MINUS(a) memset(a,0xff,sizeof(a))
//-------------------------------------------------------

int N;
int A[18],B[18];
int D[18][18];

int dp[1<<18][18];

int ok(int v) {
	ZERO(dp);
	int i,j;
	FOR(i,N) dp[1<<i][i]=1;
	for(int mask=0;mask<1<<N;mask++) {
		FOR(i,N) if(dp[mask][i]) {
			if(mask==(1<<N)-1) return 1;
			FOR(j,N) if((mask&(1<<j))==0 && D[i][j]<=v) {
				dp[mask^(1<<j)][j]=1;
			}
		}
	}
	return 0;
	
}

void solve() {
	int i,j,k,l,r,x,y; string s;
	
	cin>>N;
	FOR(i,N) cin>>A[i]>>B[i];
	FOR(x,N) FOR(y,N) D[x][y]=B[x]-A[x]+A[y];
	
	int ret=1<<20;
	for(int i=19;i>=0;i--) if(ok(ret-(1<<i))) ret-=1<<i;
	cout<<ret<<endl;
	
}


int main(int argc,char** argv){
	string s;int i;
	if(argc==1) ios::sync_with_stdio(false), cin.tie(0);
	FOR(i,argc-1) s+=argv[i+1],s+='\n'; FOR(i,s.size()) ungetc(s[s.size()-1-i],stdin);
	cout.tie(0); solve(); return 0;
}