#!/usr/bin/python
# -*- coding: utf-8 -*-

# import
from sys import stdin, setrecursionlimit
setrecursionlimit(10**8)

def int_map():
    return map(int,input().split())

def int_list():
    return list(map(int,input().split()))

def int_mtx(N):
    x = [list(map(int, stdin.readline().split())) for _ in range(N)]
    return x

def str_mtx(N):
    x = [list(stdin.readline()[:-1]) for _ in range(N)]
    return x

def print_space(l):
    return print(" ".join([str(x) for x in l]))



"""    main code    """

N = int(input())
AB = int_mtx(N)

dp = [[float("INF") for _ in range(N)] for _ in range(2**N)]
for u in range(N):
    dp[2**u][u] = 0

for s in range(2**N):
    for v in range(N):
        if s >> v & 1 == 0:
            now = float("INF")
            for u in range(N):
                if s>>u&1 == 1:
                    now = max(dp[s][u], AB[v][0] + (AB[u][1]-AB[u][0]))
                    dp[s+2**v][v] = min(dp[s+2**v][v], now)


ans = float("INF")

for u in range(N):
    ans = min(ans, dp[2**N-1][u])

print(ans)