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

#define fi first
#define se second
#define N 1005
#define smin(X, Y) ((X) < (Y) ? (X) : (Y))
pair <int,int> M[N*10];
int n, m, c[N][N], p[N];
bool viz[N];
vector <int> sol, v[N];
queue <int> Q;

bool bfs(){
    for (int i=1; i<=n; i++) viz[i] = 0;
    viz[1] = 1; Q.push(1);
    while (!Q.empty()){
        int nod = Q.front();
        Q.pop();
        if (nod == n) continue;
        for (auto it: v[nod]){
            if (viz[it] || !c[nod][it]) continue;
            viz[it] = 1; Q.push(it); p[it] = nod;
        }
    }
    return viz[n];
}

void flux(){
    while (bfs()){
        for (auto it: v[n]){
            if (!viz[it]) continue;
            int flow = 1e9;
            p[n] = it;
            for (int nod = n; nod != 1; nod = p[nod])
                flow = smin(flow, c[p[nod]][nod]);
            for (int nod = n; nod != 1; nod = p[nod]){
                c[p[nod]][nod] -= flow;
                c[nod][p[nod]] += flow;
            }
        }
    }
}

void dfs(int q){
    viz[q] = 1;
    for (auto it: v[q])
         if (!viz[it] && c[q][it]) dfs(it);
}

int main(){
    freopen("critice.in", "r", stdin);
    freopen("critice.out", "w", stdout);
    scanf("%d %d", &n, &m);
    for (int i=1, x, y, z; i<=m; i++){
        scanf("%d %d %d", &x, &y, &z);
        M[i] = {x, y};
        c[x][y] = c[y][x] = z;
        v[x].push_back(y);
        v[y].push_back(x);
    }
    flux();
    for (int i=1; i<=n; i++) viz[i] = 0;
    dfs(1);
    for (int i=1; i<=m; i++)
        if (viz[M[i].fi] != viz[M[i].se]) sol.push_back(i);
    printf("%d", sol.size());
    for (auto &it: sol) printf("\n%d", it);
    return 0;
}