#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
#define ALL(v) (v).begin(), (v).end()
#define MASK(i) (1LL << (i))
#define GETBIT(mask, i) (((mask) >> (i)) & 1)
// mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
mt19937_64 rng(1);
ll rngesus(ll l, ll r){return ((ull) rng()) % (r - l + 1) + l;}
ll max(ll a, ll b){return (a > b) ? a : b;}
ll min(ll a, ll b){return (a < b) ? a : b;}
ll LASTBIT(ll mask){return mask & (-mask);}
ll pop_cnt(ll mask){return __builtin_popcountll(mask);}
ll ctz(ll mask){return __builtin_ctzll(mask);}
ll clz(ll mask){return __builtin_clzll(mask);}
ll logOf(ll mask){return 63 - clz(mask);}
template <class T1, class T2>
bool minimize(T1 &a, T2 b){
if (a > b){a = b; return true;}
return false;
}
template <class T1, class T2>
bool maximize(T1 &a, T2 b){
if (a < b){a = b; return true;}
return false;
}
template <class T>
void printArr(T& a, string separator = " ", string finish = "\n", ostream& out = cout){
for(auto i: a) out << i << separator;
out << finish;
}
template <class T>
void remove_dup(vector<T> &a){
sort(ALL(a));
a.resize(unique(ALL(a)) - a.begin());
}
const int N = 1e5 + 69;
struct DSU{
int n;
int parent[N];
DSU(){
n = N-1;
for(int i = 0; i<=n; ++i)
parent[i] = i;
}
int find_set(int u){return (u == parent[u]) ? u : (parent[u] = find_set(parent[u]));}
bool same_set(int u,int v){return find_set(u) == find_set(v);}
bool join_set(int u, int v){
u = find_set(u), v = find_set(v);
if (u != v){
parent[v] = u;
return true;
}
return false;
}
};
DSU mst1, mst2;
vector<int> graph[N];
int last[N];
int dfs_cnt = 0;
int edge_cnt = 0;
void tarjan(int u, int p){
#define num mst1.parent
#define low mst2.parent
num[u] = low[u] = ++dfs_cnt;
for(int v: graph[u]){
if (v == p){p = -1; continue;}
if (num[v]) minimize(low[u], num[v]);
else{
tarjan(v, u);
minimize(low[u], low[v]);
if (low[v] >= num[v]){
cout << u << " " << v << "\n";
}
}
}
}
int main(void){
ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
int n, m; cin >> n >> m;
for(int i = 1; i<=m; ++i){
int u, v; cin >> u >> v;
if (mst1.join_set(u, v)){
edge_cnt++;
graph[u].push_back(v);
graph[v].push_back(u);
}
else{
mst2.join_set(u, v);
}
}
for(int i= 1; i<=n; ++i) last[mst2.find_set(i)] = i;
for(int i = 1; i<=n; ++i){
int u = last[mst2.find_set(i)], v = i;
if (u != v){
graph[u].push_back(v);
graph[v].push_back(u);
}
else last[mst2.find_set(i)] = i;
}
for(int i = 1; i<=n; ++i) mst1.parent[i] = mst2.parent[i] = 0;
for(int i = 1; i<=n; ++i) if (num[i] == 0) tarjan(i, i);
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
3676 KB |
Output is correct |
2 |
Correct |
1 ms |
3676 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
4 ms |
3932 KB |
Output is correct |
2 |
Correct |
3 ms |
3932 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
66 ms |
3900 KB |
Output is correct |
2 |
Correct |
68 ms |
3904 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
107 ms |
4104 KB |
Output is correct |
2 |
Correct |
128 ms |
4084 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
187 ms |
4692 KB |
Output is correct |
2 |
Correct |
193 ms |
4892 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
261 ms |
6636 KB |
Output is correct |
2 |
Correct |
262 ms |
15868 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
403 ms |
7076 KB |
Output is correct |
2 |
Runtime error |
418 ms |
23952 KB |
Memory limit exceeded |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
558 ms |
7560 KB |
Output is correct |
2 |
Runtime error |
485 ms |
28736 KB |
Memory limit exceeded |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
628 ms |
7556 KB |
Output is correct |
2 |
Runtime error |
615 ms |
34256 KB |
Memory limit exceeded |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
761 ms |
7356 KB |
Output is correct |
2 |
Runtime error |
847 ms |
41544 KB |
Memory limit exceeded |
3 |
Halted |
0 ms |
0 KB |
- |