N=int(input())
LR=[]
for _ in range(N):
    a,b=map(int,input().split())
    LR.append((a,b-a))
MAX=1<<N
INF=int(1e18)
dp=[[INF for _ in range(N)] for _ in range(MAX)]
for i in range(N):dp[1<<i][i]=0
for s in range(1,MAX):
    for frm in range(N):
        if s&(1<<frm)==0:continue
        for to in range(N):
            if s&(1<<to)==0:continue
            bs=s^(1<<to)
            _,r=LR[frm]
            l,_=LR[to]
            cost=max(dp[bs][frm],l+r)
            dp[s][to]=min(dp[s][to],cost)
ans=min(dp[-1])
print(ans)