#include<bits/stdc++.h>
using namespace std;

#define INF 1e9
#define N 1005
#define M 10005

int path[N];
int adj[N][N];
int n,m;
vector<int > v[N];
pair<int, int> muchii[M];
bool viz[N];
vector<int> ans;
queue<int> q;

bool bfs(){
    for(int i = 1;i<=N;i++)
        path[i]  =0;

    path[1] = -1;
    q.push(1);
    while(!q.empty()){
        int curr = q.front();
        q.pop();
        if(curr == n) continue;
        for(auto next: v[curr]){
            if(!path[next] && adj[curr][next]){
                path[next] = curr;
                q.push(next);
            }
        }
    }
    return path[n];
}

void maxflow(){
    while(bfs()){
        for(auto pred : v[n]){
            if(path[pred] > 0 && adj[pred][n]){
                int curr = n;
                path[n] = pred;
                int flow = 1e9;
                while(curr != 1){
                    flow = min(flow, adj[path[curr]][curr]);
                    curr = path[curr];
                }
                if(!flow) continue;
                curr = n;
                while(curr != 1){
                    adj[path[curr]][curr] -= flow;
                    adj[curr][path[curr]] += flow;
                    curr = path[curr];
                }
            }
        }
    }

}

void dfs1(int x){
    viz[x] = 1;
    for(auto next: v[x]){
        if(!viz[next] && adj[x][next]){
            dfs1(next);
        }
    }
}

int main(){

    freopen("critice.in", "r", stdin);
    ofstream cout("critice.out");

    scanf("%d %d",&n,&m);
    for(int i = 1;i<=m;i++){
        int a,b,c;
        scanf("%d %d %d",&a,&b,&c);
        v[a].push_back(b);
        v[b].push_back(a);
        adj[a][b] = adj[b][a] = c;
        muchii[i] = {a,b};
    }
    maxflow();

    dfs1(1);

    for(int i = 1;i<=m;i++)
        if(viz[muchii[i].first] != viz[muchii[i].second])
            ans.push_back(i);

    cout<<ans.size()<<'\n';
    for(auto i: ans){
        cout<<i<<'\n';
    }

    return 0;
}