#include <bits/stdc++.h>
#define PB push_back
#define ST first
#define ND second
#define _ ios_base::sync_with_stdio(0); cin.tie(0);
//mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
using namespace std;
using ll = long long;
using pi = pair<int,int>;
using vi = vector<int>;
const int nax = 100 * 1000 + 10, mod = 1e9 + 7, p = 31;
int n, m;
vector<pi>V[nax];
int cost[nax];
bool vis[nax];
int xr[nax];
vector<pi>num;
bool done[nax];
void dfs(int x, int par) {
vis[x] = true;
for(auto nbh : V[x]) if(nbh.ST != par) {
if(!vis[nbh.ST]) {
xr[nbh.ST] = xr[x] ^ cost[nbh.ND];
dfs(nbh.ST, x);
} else {
if(done[nbh.ND]) continue;
done[nbh.ND] = true;
num.emplace_back(xr[x] ^ xr[nbh.ST] ^ cost[nbh.ND], nbh.ND);
}
}
}
int main() {_
cin >> n >> m;
for(int a, b, c, i = 1; i <= m; ++i) {
cin >> a >> b >> c;
V[a].emplace_back(b, i);
V[b].emplace_back(a, i);
cost[i] = c;
}
dfs(1, 0);
int id = 0;
vi res = {};
vector<vi>ans = {};
for(int bit = 30; bit >= 0; --bit) {
bool any = false;
for(int i = id; i < (int)num.size(); ++i) {
if((1 << bit) & num[i].ST) {
swap(num[i], num[id]);
any = true;
break;
}
}
if(any) {
res.PB(num[id].ST);
vi tmp = {num[id].ND};
for(int i = id + 1; i < (int)num.size(); ++i) {
if(num[i].ST & (1 << bit)) {
num[i].ST ^= num[id].ST;
tmp.PB(num[i].ND);
}
}
ans.PB(tmp);
id++;
}
}
cout << id << "\n";
for(int i = 0; i < id; ++i) {
cout << res[i] << " " << (int)ans[i].size() << " ";
for(auto x : ans[i]) cout << x << " ";
cout << "\n";
}
}
