#include <fstream>
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
ifstream fi("critice.in");
ofstream fo("critice.out");

int i,j,n,m,c[1001][1001],cr[1001][1001],viz[1001],cd[10001],f[1001][1001],t[1001],flux;
vector< int > rsa;


int BFS()
{
	for (int i=1; i<=n; i++) viz[i]=0;
	int st=1,dr=1;
	cd[1]=1;
	while (st<=dr)
	{
		int nod=cd[st++];
		for (int i=1; i<=n; i++)
		{
			if (c[nod][i]>f[nod][i] && !viz[i])
			{
				viz[i]=1;
				t[i]=nod;
				cd[++dr]=i;
			}
		}
	}
	
	
	return viz[n];
}

void afis(){
	
	for (int i=1; i<=n; i++)
	{
		for (int j=1; j<=n; j++)
		{
			cout << f[i][j] << ' ';
		}
		cout << endl;
	}
	cout << endl;
	for (int i=1; i<=n; i++)
	{
		for (int j=1; j<=n; j++)
		{
			cout << c[i][j] << ' ';
		}
		cout << endl;
	}
	cout << endl;
}

int fl()
{
	int flux=0;
	for (i=1; i<=n; i++)
		for(j=1; j<=n; j++)
			f[i][j]=0;
	while (BFS())
	{
		for (i=1; i<=n; i++)
		{
			if (c[i][n]>f[i][n])
			{
				int fmin=c[i][n]-f[i][n];
				for (j=i; j!=1; j=t[j])
					fmin=min(fmin,c[t[j]][j]-f[t[j]][j]);
				for (j=i; j!=1; j=t[j])
				{
					f[t[j]][j]+=fmin;
					f[j][t[j]]-=fmin;
				}
				f[i][n]+=fmin;
				f[n][i]-=fmin;
				flux+=fmin;
			}
		}
	}
	return flux;
}

int main(){
	
	fi >> n >> m;
	for (i=1; i<=m; i++)
	{
		int x,y,z;
		fi >> x >> y >> z;
		c[x][y]=c[y][x]=z; cr[x][y]=cr[y][x]=i;
	}
	
	
	flux=fl();
	
	for (int i=1; i<=n; i++)
	{
		for (int j=1; j<=n; j++)
		{
			if (f[i][j]==c[i][j] && f[i][j]) 
			{
				c[i][j]++; c[j][i]++;
				if (fl()>flux) rsa.push_back(cr[i][j]);
				c[i][j]--; c[j][i]--;
			}
		}
	}
	
	sort(rsa.begin(),rsa.end());
	
	fo << rsa.size() << endl;
	for (size_t k=0; k<rsa.size(); k++)
		fo << rsa[k] << endl;
	
	return 0;
}