## https://yukicoder.me/problems/no/2040


MOD = 998244353

def main():
    N, M = map(int, input().split())
    items = []
    for _ in range(M):
        i1, i2, score = map(int, input().split())
        items.append((i1, i2, score))

    items_map = {}
    for b, a, score in items:
        if a not in items_map:
            items_map[a] = []
        items_map[a].append((b, score))
    
    bit_counts = [[] for _ in range(N + 1)]
    for bit in range(2 ** N):
        bit_count = 0
        for i in range(N):
            if bit & (1 << i) > 0:
                bit_count += 1
        bit_counts[bit_count].append(bit)
    
    dp = [-1] * (2 ** N)
    dp[0] = 0
    for bit_count in range(N):
        for bit in bit_counts[bit_count]:
            for j in range(N):
                if (1 << j) & bit == 0:
                    new_bit = (1 << j) | bit

                    add_score = 0
                    if j in items_map:
                        for b, score in items_map[j]:
                            if (1 << b) & bit > 0:
                                add_score += score
                    
                    dp[new_bit] = max(dp[new_bit], dp[bit] + add_score)
    
    print(dp[2 ** N - 1])












if __name__ == "__main__":
    main()