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#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize ("O3")
#pragma GCC optimize ("O2")
#pragma GCC optimize ("O1")
#pragma GCC optimize ("unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#pragma GCC optimize ("fast-math")
#define ezurect int T; cin >> T; while(T--){solve();}
const int N = 1e3 + 1, M = 4e5 + 1, mod = 666013;
int n, m;
vector<int> liste[N];
vector<vector<int>> cost(N, vector<int>(N)), f(N, vector<int>(N)), mamata(N, vector<int>(N));
vector<int> p(N);
vector<int> viz(N);
vector<pair<int, int>> edges;
int bfs(){
queue<int> q;
q.push(1);
p.assign(N, -1);
p[1] = 0;
while(!q.empty()){
int nod = q.front();
q.pop();
if(nod == n){
continue;
}
for(auto i : liste[nod]){
if(p[i] == -1 && f[nod][i] < cost[nod][i]){
p[i] = nod;
q.push(i);
}
}
}
if(p[n] < 0) return 0;
return 1;
}
int MaxFlow(){
int maxflow = 0;
while(bfs()){
int t = n;
for(auto i : liste[t]){
if(f[i][t] == cost[i][t] || p[i] == -1){
continue;
}
p[t] = i;
int minim = 1e9;
for(int j = t; j != 1; j = p[j]){
minim = min(minim, cost[p[j]][j] - f[p[j]][j]);
}
for(int j = t; j != 1; j = p[j]){
f[p[j]][j] += minim;
f[j][p[j]] -= minim;
}
maxflow += minim;
}
}
return maxflow;
}
void dfs(int nod){
viz[nod] = 1;
for(auto i : liste[nod]){
if(viz[i] == 0 && f[nod][i] < cost[nod][i]){
dfs(i);
}
}
}
int main(){
ifstream fin("critice.in");
ofstream fout("critice.out");
fin.tie(0)->sync_with_stdio(0);
fin >> n >> m;
for(int i = 1; i <= m; i++){
int u, v, c;
fin >> u >> v >> c;
liste[u].push_back(v);
liste[v].push_back(u);
cost[u][v] = c;
cost[v][u] = c;
mamata[u][v] = mamata[v][u] = i;
edges.push_back({u, v});
}
int pula = MaxFlow();
vector<int> sol;
for(auto i : edges){
cost[i.first][i.second]++;
cost[i.second][i.first]++;
for(auto j : edges){
f[j.first][j.second] = f[j.second][j.first] = 0;
}
if(MaxFlow() > pula){
sol.push_back(mamata[i.first][i.second]);
assert(i.first != 1 || i.second != 1);
}
cost[i.first][i.second]--;
cost[i.second][i.first]--;
}
fout << sol.size() << '\n';
sort(sol.begin(), sol.end());
for(auto i : sol){
fout << i << '\n';
}
}