#define inf 0x3f3f3f3f

#define maxm 100000

#define maxn 10000

#define eps 1e-9

struct node

{

  int u ;

  int v,next,id;

  double w;

  void init(int u1,int v1,double w1)

  {

    u = u1;

    v = v1;

    w = w1;

  }

};

node e1[maxn];

int head[maxn];

int cnt ;

int cnt1;

node edge[maxn];

int sgn(double x) {         //return -1 0 1

  return x < -eps ? - : x > eps;

}

void init()

{

  memset(head,-,sizeof(head));

  cnt =  ;

}

void add(int u,int v,int id,double w)

{

  edge[cnt].u = u;

  edge[cnt].v = v;

  edge[cnt].w = w;

  edge[cnt].id = id;

  edge[cnt].next = head[u];

  head[u] = cnt ++ ;

  edge[cnt].u = v;

  edge[cnt].v = u;

  edge[cnt].w = ;

  edge[cnt].id = id;

  edge[cnt].next = head[v];

  head[v] = cnt ++ ;

}

int dis[maxn];

int pre[maxn],cur[maxn],gap[maxn];

int s,t,nn;

int sap()

{

  double flow,aug;

  int u;

  int flag;

  int i;

  flow=;

  aug=inf;

  for(i=; i<nn; i++)

  {

    cur[i]=head[i];

    gap[i]=;

    dis[i]=;

  }

  gap[s]=nn;

  u=s;

  pre[s]=s;

  while(dis[s]<nn)

  {

    flag=;

    for(int &j=cur[u]; j!=-; j=edge[j].next)

    {

      //cur[u]=j;

      int v=edge[j].v;

      if(edge[j].w>&&dis[u]==dis[v]+)

      {

        flag=;

        if(edge[j].w<aug)aug=edge[j].w;

        pre[v]=u;

        u=v;

        if (u==t)

        {

          flow+=aug;

          while(u!=s)

          {

            u=pre[u];

            edge[cur[u]].w-=aug;

            edge[cur[u]^].w+=aug;

            //why?解释偶数异或1为偶数+1，奇数异或1为奇数-1，

            //显然我们存的边是从0开始存的，

            //所以偶数,偶数+1是残量网格中的两条边(无向边)

          }

          aug=inf;

        }

        break;

      }

    }

    if (flag) continue;

    int mindis=nn;

    for(int j=head[u]; j!=-; j=edge[j].next)

    {

      int v=edge[j].v;

      if (edge[j].w>&&dis[v]<mindis)

      {

        mindis=dis[v];

        cur[u]=j;

      }

    }

    if (--gap[dis[u]]==)//间隙优化

    {

      break;

    }

    dis[u]=mindis+;

    gap[dis[u]]++;

    u=pre[u];

  }

  return flow;

}

bool xxx[maxn];

int n,m;

double judge(double lda)

{

  memset(xxx,,sizeof(xxx));

  init();

  double res = 0.0;

  for(int i = ; i <= m  ; i ++)

  {

    double tmp ;

    tmp = e1[i].w - lda;

    if( tmp >= )

      add(e1[i].u,e1[i].v,i,tmp) , add(e1[i].v,e1[i].u,i,tmp); // 注意

    else

    {

      res += tmp;

      xxx[i] =  ;

    }

    //if(sgn(tmp) < 0 )

    //    res += tmp ;

    //else add(e1[i].u,e1[i].v,i,tmp);

  }

  s = ;

  t = n ;

  nn = t + ;

  res += sap();

  return res;

}

queue<int> q;

int col[maxn];

bool vis[maxn];

void bfs(int st,int color)

{

  memset(vis,,sizeof(vis));

  memset(col,,sizeof(col));

  while(!q.empty()) q.pop();

  q.push(st);

  vis[st] = ;

  col[st] = color;

  while(!q.empty())

  {

    int u = q.front();

    q.pop();

    for(int i = head[u] ; i != -; i = edge[i].next)

    {

      int v = edge[i].v;

      if(sgn(edge[i].w) >  && vis[v] ==  )

      {

        vis[v] = ;

        col[v] = color;

        q.push(v);

      }

    }

  }

  return ;

}

vector<int> ans ;

void getst(double lda)

{

  bfs(,);

  ans.clear();

  for(int i =  ; i <= m ; i ++ )     // 注意

  {

    if(!xxx[i])

    {

      if(col[e1[i].u] != col[e1[i].v] )

      {

        ans.push_back(i);

      }

    }

    else ans.push_back(i);

  }

  int size = ans.size();

  sort(ans.begin(),ans.end());

  printf("%d\n",size);

  for(int i = ; i < size ; i++ )

  {

    printf("%d",ans[i]);

    if(i != size -  ) printf(" ");

    else printf("\n");

  }

}

int main()

{

  int cas;

  cas =  ;

  while(scanf("%d%d",&n,&m)!=EOF)

  {

    cnt1 =  ;

    int u,v;

    double w;

    double L,R;

    L = eps;

    for(int i =  ; i <= m; i ++ )

    {

      scanf("%d%d%lf",&u,&v,&w);

      e1[i].init(u,v,w);

      R = max(R , w);

    }

    double mid ;

    for(int i =  ; i <  ; i ++ )

      // while( R - L > eps )

    {

      mid = ( L + R ) / 2.0;

      double tmp = judge(mid);

      if(sgn(tmp ) >  )    // 判断

        L = mid + eps;

      else R = mid;

    }

    if(cas !=  ) printf("\n");

    cas ++ ;

    judge(L);

    getst(L);

  }

  return ;

}