use std::io::{self,Read};

fn main(){

  let inf = 100_000;
  let mut buf = String::new();
  io::stdin().read_to_string(&mut buf).unwrap();
  let mut lines = buf.lines();
  
  let n: usize = lines.next().unwrap().parse().unwrap();
  let s: usize = 1 << n;
  
  let book:Vec<(i32,i32)> = lines.by_ref().take(n).map(|line| {
      let v:Vec<i32> = line.split_whitespace().map(|x| x.parse().unwrap()).collect();
      (v[0], v[1])
    }).collect();
  
  let mut dp:Vec<Vec<i32>> = (0..n).map(|_i| vec![inf; s] ).collect();
  for i in 0 .. n {
    dp[i][1 << i] = 0;
  }
  
  for state in 1 .. s {
    let (used, unused): (Vec<usize>, Vec<usize>) = (0 .. n).partition(|x| state  & (1_usize << x) > 0 );
    for &j in unused.iter() {
      dp[j][ state | (1_usize << j)] = used.iter()
        .fold(inf,|m, &i| std::cmp::min(m, std::cmp::max(dp[i][state], book[i].1 - book[i].0 + book[j].0)));
    }
  }
  
  println!("{}", (0..n).map(|i| dp[i][s - 1] ).min().unwrap());
}