n = int(input())
d = [list(map(int,input().split())) for _ in range(n)]
N = 1<<n
INF = 1<<30
dp = [-INF]*N
dp[0] = 0
lst = []
for i in range(n):
    for j in range(i+1,n):
        lst.append(((1<<i)+(1<<j),d[i][j]))
for mask in range(N):
    if dp[mask]==INF: continue
    for k,v in lst:
        if mask&k: continue
        dp[mask|k] = max(dp[mask|k], dp[mask] + v)
print(dp[-1])