import sys
readline = sys.stdin.readline

N = int(readline())
L = []
for i in range(N):
    L.append(list(map(int, readline().split())))
    
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])

print(ans)