import sys
readline=sys.stdin.readline

N,M=map(int,readline().split())
item=[[] for i in range(N)]
for _ in range(M):
    x,y,s=map(int,readline().split())
    item[y].append((x,s))
dp=[0]*(1<<N)
for bit in range(1<<N):
    for y in range(N):
        if bit&1<<y:
            dp[bit]=max(dp[bit],dp[bit^1<<y]+sum(s for x,s in item[y] if bit&1<<x))
ans=dp[-1]
print(ans)