#include<bits/stdc++.h>
using namespace std;
typedef  pair<pair<int,int>,int> trei;
ifstream in("critice.in");
ofstream out("critice.out");
int n,m;
int tata[1001];
vector<vector<int>>muchii(1001,vector<int>(0));
vector<trei>tunel;
int val[1001][1001];
bool bfs()
{bool ok=0;
for(int i=2;i<=n;i++)
tata[i]=0;
queue<int>q;
q.push(1);
while(!q.empty())
{int nod=q.front();
q.pop();
    for(auto x:muchii[nod])
    if(val[nod][x]<=0||tata[x])continue;
    else
   {
    if(x==n){ok=1;tata[n]=63;}
    else
    {q.push(x);
        tata[x]=nod;
    }}
}

    return ok;
}
int main()
{in>>n>>m;
tata[1]=1;
for(int i=1;i<=m;i++)
{int x,y,z;

in>>x>>y>>z;
val[x][y]=val[y][x]=z;
tunel.push_back({{x,y},z});
muchii[x].push_back(y);
muchii[y].push_back(x);
}
while(bfs())
for(auto x:muchii[n])
   if(val[x][n]&&tata[x])
   {int ok=1;
       int vmin=val[x][n];
   int fiul=x,tatal=tata[x];
   while(fiul!=1&&ok)
   {vmin=min(vmin,val[tatal][fiul]);
   fiul=tatal;
   tatal=tata[tatal];
       if(vmin<=0)ok=0;
   }
     if(ok)
     {val[x][n]-=vmin;
         val[n][x]+=vmin;
         fiul=x,tatal=tata[x];
   while(fiul!=1)
   {val[tatal][fiul]-=vmin;
   val[fiul][tatal]+=vmin;

   fiul=tatal;
   tatal=tata[tatal];
   }

     }
   }
    vector<int>rezultat;

    for(int i=0;i<tunel.size();i++)
{int x=tunel[i].first.first,y=tunel[i].first.second;
bool ok=0;
if(!val[x][y])
{val[x][y]=1;
ok|=bfs();
val[x][y]=0;
}
if(!val[y][x])
{val[y][x]=1;
ok|=bfs();
    val[y][x]=0;
}
if(ok)
    rezultat.push_back(i+1);
}
out<<rezultat.size();
for(auto x:rezultat)
out<<'\n'<<x;

}