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| #include <bits/stdc++.h>
using namespace std;
const int maxm = 4e5+10;
const int maxn = 2e5+10;
struct Edge{
int f,t,next;
Edge(int f = 0,int t = 0,int next = 0):f(f),t(t),next(next){}
}edge[maxm];
int cnt,head[maxm],vis[maxm],dep[maxn],in[maxn],dict[maxn];
void addedge(int f,int t){
edge[cnt] = Edge(f,t,head[f]);
head[f] = cnt++;
}
bool ok = 1;
pair<int,int>Node[maxn];
void BFS(int n){
int qwq = 0;
queue<int>q;
for(int i = 1;i <= n;i++)if(!in[i]){
q.push(i);
vis[i] = 1;
dep[i] = 0;
}
if(q.empty())ok = 0;
while(!q.empty()){
int u = q.front();
q.pop();
dep[u] = ++qwq;
for(int i = head[u];~i;i = edge[i].next){
int v = edge[i].t;
if(--in[v]){
continue;
}
q.push(v);
}
}
if(qwq != n)ok = 0;
}
signed main(){
ios::sync_with_stdio(0);
cin.tie(0);
int t;
cin >> t;
while(t--){
ok = 1;
int n,m;
cin >> n >> m;
for(int i = 0;i <= n;i++){
head[i] = -1;
dep[i] = dict[i] = in[i] = vis[i] = 0;
}
for(int i = 1;i <= m;i++){
int opt,f,t;
cin >> opt >> f >> t;
Node[i] = {f,t};
if(opt){
addedge(f,t);
in[t]++;
dict[i] = 1;
}
}
BFS(n);
if(!ok){
cout << "NO\n";
}
else{
cout << "YES\n";
for(int i = 1;i <= m;i++){
int & f = Node[i].first,& t = Node[i].second;
if(dep[f] > dep[t])cout << t << " " << f << endl;
else cout << f << " " << t << endl;
}
}
}
return 0;
}
|