#include <bits/stdc++.h>
using namespace std;
int n,m,a,b,c,go[14][14], pt[14][1<<14],dp[1<<14];
int main(){
  scanf("%d%d",&n,&m);
  for(int i=0;i<m;i++){
    scanf("%d%d%d",&a,&b,&c);
    go[a][b]=c;pt[a][0]+=c;
  }
  for (int i = 0; i < n; i++){
    int high = 1;
    int hst = 0;
    for (int j = 1; j < 1 << n; j++){
        if (!(j >> i & 1))
          pt[i][j] = pt[i][j ^ high] - go[i][hst];
        if(j+1==high<<1){high<<=1;hst++;}
    }
  }
  for (int i = 0; i < 1 << n; i++){
    for (int j = 0; j < n; j++){
        if ((i >> j & 1)) continue;
        dp[i | (1 << j)] = max(dp[i | (1 << j)], dp[i] + pt[j][i]);
    }
  }
  printf("%d\n",dp[(1 << n) - 1]);
}