N = int(input())
AB = [list(map(int,input().split())) for i in range(N)]

# dp[S][v] = 使用した本の集合S, 最後の本v, 最小値

INF = 1 << 60
dp = [[INF] * N for i in range(1 << N)]

for i in range(N):
    dp[1 << i][i] = 0
    
for status in range(1 << N):
    for from_v in range(N):
        if (status >> from_v) & 1 == 0:
            continue
        for to_v in range(N):
            if (status >> to_v) & 1:
                continue
            next_status = status | (1 << to_v)
            new_gap = (AB[from_v][1] - AB[from_v][0]) + AB[to_v][0]
            dp[next_status][to_v] = min(dp[next_status][to_v], max(dp[status][from_v], new_gap))

print(min(dp[-1]))