n = int(input())
a = [0]*n
b = [0]*n
for i in range(n):
    a[i],b[i] = map(int,input().split())

N = 1<<n
INF = 1<<30
dp = [[INF]*n for _ in range(N)]
for i in range(n):
    dp[1<<i][i] = 0

for mask in range(N):
    for j in range(n):
        if mask>>j&1: continue
        res = INF
        for i in range(n):
            if mask>>i&1==0: continue
            res = min(res,max(dp[mask][i],a[j]+b[i]-a[i]))
        dp[mask|(1<<j)][j] = min(dp[mask|(1<<j)][j], res)

print(min(dp[-1]))