//HAPPY BIRTHDAY!!!
#include <bits/stdc++.h>
#define push_back emplace_back
using namespace std;
typedef pair<int,int> ii;
struct UFDS{
int n;
int p[100005];
void init(int _n){
n = _n;
for(int i = 1;i <= n;i++) p[i] = i;
}
int find(int u){
if(p[u] == u) return u;
else{
p[u] = find(p[u]);
return p[u];
}
}
void unionSet(int u, int P){
u = find(u); P = find(P);
if(u == P) return;
p[u] = P;
}
} tree, bridge;
vector<int> nodes[100005];
int p[100005];
int depth[100005];
vector<ii> possible;
void reroot(int u){
vector<int> order;
while(u != 0){
order.push_back(u);
u = p[u];
}
int sz = order.size(); order.push_back(0);
for(int i = 0;i < sz;i++){
p[order[i+1]] = order[i];
depth[order[i]] = sz-i-1;
}
order.clear();
}
signed main(){
ios_base::sync_with_stdio(false); cin.tie(0);
int n, E; cin >> n >> E;
tree.init(n+2); bridge.init(n+2);
for(int i = 1;i <= n;i++) nodes[i].emplace_back(i);
while(E--){
int u, v; cin >> u >> v;
if(bridge.find(u) == bridge.find(v)) continue;
if(tree.find(u) == tree.find(v)){ ///bridge formed
vector<int> path;
while(u != v){
if(depth[u] > depth[v]) swap(u,v); ///v is deeper now
path.push_back(v);
v = p[v];
}
int P = u;
//cout << P << "\n";
for(int x : path){
p[x] = P;
p[x] = P;
depth[x] = depth[P]+1;
bridge.unionSet(x, P);
}
}
else{ ///connect two trees to 1 tree
int U = tree.find(u), V = tree.find(v);
//if(nodes[U].size() > nodes[V].size()){
// swap(U,V);
// swap(u,v);
//}
tree.unionSet(U, V);
reroot(u);
p[u] = v;
while(!nodes[U].empty()){
int B = nodes[U].back();
depth[B] += depth[v] + 1;
nodes[V].emplace_back(B);
nodes[U].pop_back();
}
//cout << u << " " << v << ":\n";
//for(int i = 1;i <= n;i++) cout << p[i] << " ";
//cout << "\n";
//for(int i = 1;i <= n;i++) cout << depth[i] << " ";
//cout << "\n";
possible.push_back(u,v);
}
}
for(ii e : possible){
if(bridge.find(e.first) != bridge.find(e.second)){
cout << e.first << " " << e.second << "\n";;
}
}
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
6 ms |
2688 KB |
Output is correct |
2 |
Incorrect |
6 ms |
2688 KB |
Wrong number of edges |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
41 ms |
15480 KB |
Wrong number of edges |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
122 ms |
11740 KB |
Output is correct |
2 |
Incorrect |
111 ms |
4864 KB |
Wrong number of edges |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
305 ms |
57084 KB |
Memory limit exceeded (if you are sure your verdict is not MLE, please contact us) |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
186 ms |
65540 KB |
Execution killed with signal 9 (could be triggered by violating memory limits) |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
227 ms |
65540 KB |
Execution killed with signal 9 (could be triggered by violating memory limits) |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
208 ms |
65540 KB |
Execution killed with signal 9 (could be triggered by violating memory limits) |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
225 ms |
65540 KB |
Execution killed with signal 9 (could be triggered by violating memory limits) |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
223 ms |
65540 KB |
Execution killed with signal 9 (could be triggered by violating memory limits) |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
237 ms |
65536 KB |
Execution killed with signal 9 (could be triggered by violating memory limits) |
2 |
Halted |
0 ms |
0 KB |
- |