N=int(input())
dict={}
li=[]
for i in range(N-1):
    li=input().split()
    for j in range(N-i-1):
        dict[(i,N-j-1)]=int(li[N-j-1])
else:
    li=input()
mydict=sorted(dict.items(),key=lambda x: x[1],reverse=True)
myN=len(mydict)
ans=0
for k in range(myN//2):
    x_set=set()
    y_set=set()
    x_set.add(mydict[k][0][0])
    y_set.add(mydict[k][0][0])
    sum=mydict[k][1]
    cnt=1
    sum_cnt=1
    while sum_cnt<(N/2):
        if not(mydict[k+cnt][0][0] in x_set or mydict[k+cnt][0][1] in y_set):
            sum+=mydict[k+cnt][1]
            sum_cnt+=1
            cnt+=1
        else:
            cnt+=1
    if sum > ans:
        ans=sum
print(ans)