#include <bits/stdc++.h>
using namespace std;
void fastIO(){ios_base::sync_with_stdio(false),cin.tie(0);}
#define int long long
#define f first
#define s second
const int MAXV = 100'020;
const int LOG = 30;
int V, E;
struct Edge {
int to, cost, idx;
};
vector<Edge> adj[MAXV];
int depth[MAXV];
int rootPath[MAXV];
bool isChange[MAXV];
int valChange[MAXV];
vector<pair<int,vector<int>>> ans;
void dfs (int node, int par) {
for (Edge nxt : adj[node]) {
int child = nxt.to, cost = nxt.cost, idx = nxt.idx;
if (child == par) {
continue;
}
else if (depth[child] == -1) {
depth[child] = depth[node] + 1;
rootPath[child] = rootPath[node] ^ cost;
dfs(child, node);
}
else if (depth[child] < depth[node]) {
isChange[idx] = true;
int underCost = rootPath[node] ^ rootPath[child];
int xorVal = cost ^ underCost;
valChange[idx] = xorVal;
}
}
}
signed main() {
fastIO();
cin >> V >> E;
for (int i = 0; i < E; i++) {
int u, v, c;
cin >> u >> v >> c;
u--, v--;
adj[u].push_back({v, c, i});
adj[v].push_back({u, c, i});
}
fill(depth, depth+V, -1);
depth[0] = 0;
dfs(0, -1);
vector<pair<vector<int>,int>> process(LOG);
for (int i = 0; i < LOG; i++) {
process[i].s = i;
}
for (int idx = 0; idx < E; idx++) {
if (isChange[idx]) {
for (int log = 0; log < LOG; log++) {
if (valChange[idx] & (1 << log)) {
process[log].f.push_back(idx);
}
}
}
}
sort(process.begin(), process.end());
// for (int log = 0; log < LOG; log++) {
// cerr << process[log].s << ": ";
// for (int idx : process[log].f) {
// cerr << idx << " ";
// }
// cerr << "\n";
// }
vector<int> idxProcess;
int valXor = 0;
for (int log = 0; log < LOG; log++) {
if (log != 0 && process[log].f != process[log-1].f) {
if (!idxProcess.empty()) {
ans.push_back(make_pair(valXor, idxProcess));
}
idxProcess.clear();
valXor = 0;
}
for (int idx : process[log].f) {
idxProcess.push_back(idx);
}
valXor ^= (1 << process[log].s);
}
if (!idxProcess.empty()) {
ans.push_back(make_pair(valXor, idxProcess));
idxProcess.clear();
}
cout << (int)ans.size() << "\n";
for (pair<int,vector<int>> on : ans) {
sort(on.s.begin(), on.s.end());
on.s.erase(unique(on.s.begin(), on.s.end()), on.s.end());
cout << on.f << " " << (int)on.s.size() << " ";
for (int idx : on.s) {
cout << idx+1 << " ";
}
cout << "\n";
}
}
