#include<cstdio>
#include<cstring>
#include<vector>
#include<queue>
#include<bitset>
#include<algorithm>
#define infile "critice.in"
#define outfile "critice.out"
#define n_max 1005
#define INF 1<<30
#define pb push_back
#define FOR(g) \
   for(vector<int> ::iterator it = g.begin(); it!=g.end(); ++it)
using namespace std;


vector < int > v[n_max], sol;

int T[n_max], T1[n_max], T2[n_max];

int C[n_max][n_max], F[n_max][n_max], edge[n_max][n_max];

int N, M;


void citeste()
{
	freopen(infile,"r",stdin);
	
	scanf("%d %d", &N, &M);
	
	int x, y, cap;
	
	for(int i=1;i<=M;i++)
	{
		scanf("%d %d %d",&x, &y, &cap);
		
		v[x].pb(y);
		v[y].pb(x);
		
		C[x][y] = C[y][x] = cap;	
		edge[x][y] = edge[y][x] = i;
	}
	
	fclose(stdin);
}


int bfs(int S, int D, int *T)
{
	queue < int > q;
	
	q.push(S);
	T[S] = S;
	
	while(!q.empty())
	{
		int x = q.front();
		q.pop();
		
		if(x == D)
			return 1;
		
		FOR(v[x])
			if(!T[*it] && C[x][*it] - F[x][*it] > 0)
			{
				q.push(*it);
				T[*it] = x;
			}
	}
	
	return 0;
}



void rezolva()
{	
	while(bfs(1, N, T))
	{
		FOR(v[N])
		{
			if(C[*it][N] == F[*it][N] || !T[*it])
				continue;
			
			int flux = INF;
			T[N] = *it; 
		
			for(int i = N; i!=1; i = T[i])
				flux = min(flux, C[T[i]][i] - F[T[i]][i]);
		
			for(int i = N; i!=1; i = T[i])
				F[T[i]][i] += flux, F[i][T[i]] -= flux;
		}
		memset(T,0,sizeof(T));
	}
	
	bfs(1,N,T1);
	bfs(N,1,T2);
	
	for(int i=1; i<=N; i++)
		FOR(v[i])
			if(C[i][*it] == F[i][*it] && T1[i] && T2[*it])
				sol.pb(edge[i][*it]);
}



void afiseaza()
{
	freopen(outfile,"w",stdout);
	
	printf("%d\n",sol.size());
	
	FOR(sol)
	    printf("%d ",*it);
	
	fclose(stdout);
}


int main()
{
	citeste();
	rezolva();
	afiseaza();
	
	return 0;
}