import sys
readline = sys.stdin.readline
from random import *
from time import *

N = int(readline())
sTime = time()
L = []
for i in range(N):
    L.append(list(map(int, readline().split())))
    
def f(tt, val):
    A = [0] * 64
    B = [0] * 64
    for s in range(1 << 6):
        for i in range(N//2):
            for j in range(i + 1, N//2):
                v = 1
                for k in range(6):
                    if (s >> k) & 1:
                        v *= max(L[i][k], L[j][k])
                A[s] = max(A[s], v)
                
    for s in range(1 << 6):
        for i in range(N//2, N):
            for j in range(i + 1, N):
                v = 1
                for k in range(6):
                    if (s >> k) & 1:
                        v *= max(L[i][k], L[j][k])
                B[s] = max(B[s], v)
                
    ans = 0
    for i in range(1 << 6):
        ans = max(ans, A[i] * B[63 - i])
    return ans

ans = 0
while time() - sTime < 3.0:
        shuffle(L)
        ans = max(ans, f(sTime, ans))
print(ans)