from collections import defaultdict

n, m = map(int, input().split())
G = defaultdict(list)
for _ in range(m):
    a, b, p = map(int, input().split())
    G[a].append((b, p))
DP = [[-1 for _ in range(n)] for _ in range(1 << n)]
for i in range(n):
    DP[1 << i][i] = 0
for bit in range(1 << n):
    for i in range(n):
        if (bit >> i) & 1:
            if DP[bit][i] != -1:
                for j, p in G[i]:
                    if (bit >> j) & 1 == 0:
                        nbit = bit | (1 << j)
                        DP[nbit][j] = max(DP[nbit][j], DP[bit][i] + p)
ans = 0
for bit in range(1 << n):
    for i in range(n):
        if (bit >> i) & 1:
            ans = max(ans, DP[bit][i])
print(ans)