#!/usr/bin/env python3
# %%
import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines


# %%
N = int(readline())
m = map(int, read().split())
AB = list(zip(m, m))

# %%
A, B = zip(*AB)

# # %%
INF = 10 ** 18
dp = [[INF] * N for _ in range(1 << N)]
for n in range(N):
    dp[1 << n][n] = 0

for subset in range(1 << N):
    for newbook in range(N):
        if subset & (1 << newbook):
            continue
        newset = subset | (1 << newbook)
        for lastbook in range(N):
            x = max(dp[subset][lastbook], B[lastbook] - A[lastbook] + A[newbook])
            if dp[newset][newbook] > x:
                dp[newset][newbook] = x

# %%
print(min(dp[-1]))