#include <bits/stdc++.h>
using namespace std;
int n, m, s, t;
const int maxn = 1e6 + 5;
struct node
{
    int id, nxt, flow;
} edge[maxn << 1];
int hd[maxn], len = 1, dep[maxn], cur[maxn], dfn[maxn], low[maxn], flag[maxn], vis[maxn], w[maxn], mx = -1, mi, x[maxn], y[maxn], cnt, maxx, minn, siz, tmx, tmn;
vector<pair<int, int>> vec[maxn], os;
int mxx, mnn;
void add(int x, int y, int f)
{
    edge[++len].id = y;
    edge[len].nxt = hd[x];
    edge[len].flow = f;
    hd[x] = len;
}
void Add(int x, int y, int f)
{
	add(x, y, f);
	add(y, x, 0);
}
int bfs()
{
    queue<int> q;
    for (int i = 1; i <= cnt; i++) dep[i] = 0;
    dep[s] = 1;
    q.emplace(s);
    while (!q.empty())
    {
        int tmp = q.front();
        q.pop();
        for (int i = hd[tmp]; i; i = edge[i].nxt)
            if (!dep[edge[i].id] && edge[i].flow)
                dep[edge[i].id] = dep[tmp] + 1, q.emplace(edge[i].id);
    }
    return dep[t];
}
int dinic(int now, int flow)
{
    if (!flow) return 0;
    if (now == t) return flow;
    int tmp = 0;
    for (int &i = cur[now]; i; i = edge[i].nxt)
        if (dep[edge[i].id] == dep[now] + 1 && edge[i].flow)
        {
            int tmp2 = dinic(edge[i].id, min(flow, edge[i].flow));
            edge[i].flow -= tmp2, flow -= tmp2, tmp += tmp2, edge[i ^ 1].flow += tmp2;
            if (!flow) return tmp;
        }
    return tmp;
}
void tarjan(int now, int fa)
{
	dfn[now] = low[now] = ++cnt;
	for (auto j : vec[now])
	{
		int i = j.first;
		if (i != fa)
		{
			if (!dfn[i])
			{
				tarjan(i, now);
				low[now] = min(low[now], low[i]);
				if (low[i] == dfn[i])
					flag[j.second] = 1;
			}
			else low[now] = min(low[now], dfn[i]);
		}
	}
}
void dfs(int now)
{
	siz++;
	vis[now] = 1;
	for (auto i : vec[now])
	{
		if (flag[i.second]) continue;
		maxx = max(maxx, w[i.second]), minn = min(minn, w[i.second]);
		if (!vis[i.first])
			dfs(i.first);
	}
}
int id[maxn];
void gt(int now, int fa)
{
	vis[now] = 1;
	for (auto i : vec[now])
	{
		if (i.first == fa || flag[i.second]) continue;
		if (!mxx && w[i.second] == tmx) mxx = i.second;
		else if (!mnn && w[i.second] == tmn) mnn = i.second;
		cnt++;
		add(now, cnt, 1);
		os.emplace_back(len, i.second);
		add(cnt, now, 1);
		os.emplace_back(len, i.second);
		add(cnt, i.first, 1);
		os.emplace_back(len, i.second);
		add(i.first, cnt, 1);
		os.emplace_back(len, i.second);
		id[i.second] = cnt;
		if (!vis[i.first])
			gt(i.first, now);
	}
}
vector<int> so;
void ga(int now)
{
	if (now <= n) so.emplace_back(now);
	for (int i = hd[now]; i; i = edge[i].nxt)
		if (!edge[i].flow)
			return edge[i].flow = 1, ga(edge[i].id);
}
signed main()
{
    ios::sync_with_stdio(0);
    cin.tie(0), cout.tie(0);
    cin >> n >> m;
    for (int i = 1; i <= m; i++)
    {
    	int u, v;
    	cin >> u >> v >> w[i];
    	x[i] = u, y[i] = v;
    	vec[u].emplace_back(v, i);
    	vec[v].emplace_back(u, i);
	}
	tarjan(1, 0);
	for (int i = 1; i <= n; i++)
		if (!vis[i])
		{
			minn = 1e9, maxx = -1e9, siz = 0;
			dfs(i);
			if (siz != 1 && maxx - minn > mx) mx = maxx - minn, tmx = maxx, tmn = minn, mi = i;
		}
	cout << mx << '\n';
	cnt = n;
	memset(vis, 0, sizeof(vis));
	gt(mi, 0);
	s = id[mnn], t = id[mxx];
//	if (n >= 100)
//	cout << tmx << ' ' << tmn << ' ' << mi << ' ' << mnn << ' ' << mxx << '\n';
	bfs();
	for (int i = 1; i <= cnt; i++) cur[i] = hd[i];
	dinic(s, 1);
	bfs();
	for (int i = 1; i <= cnt; i++) cur[i] = hd[i];
	dinic(s, 1);
	ga(s);
	reverse(so.begin(), so.end());
	ga(s);
	cout << so.size() << '\n';
	for (int i : so) cout << i << ' ';
    return 0;
}