#include<stdio.h>
#include<stdlib.h>

#define MAX(a,b) ((a)>(b)?(a):(b))
#define MIN(a,b) ((a)<(b)?(a):(b))

#define POS(i,j) ((i)*(1<<n)+(j))

typedef struct book{
  int a,b;
} book;

int calc(int l,int bit,book *p,int n,int *dp){
  if(dp[POS(l,bit)]>0) return dp[POS(l,bit)];
  if(bit==0) return 0;
  int local=2001;
  for(int i=0;i<n;i++){
    if(((bit>>i)&1)==0) continue;
    int v=calc(i,bit^(1<<i),p,n,dp);
    local=MIN(local,MAX(v,p[i].a+(p[l].b-p[l].a)));
  }
  dp[POS(l,bit)]=local;
  return local;
}

void run(void){
  int n;
  scanf("%d",&n);
  book p[18];
  int i;
  for(i=0;i<n;i++) scanf("%d%d",&p[i].a,&p[i].b);
  int *dp=(int *)calloc(n*(1<<n),sizeof(int));
  int ans=2000;
  for(i=0;i<n;i++){
    int v=calc(i,((1<<n)-1)^(1<<i),p,n,dp);
    ans=MIN(ans,v);
  }
  printf("%d\n",ans);
}

int main(void){
  run();
  return 0;
}