#include <bits/stdc++.h>
using namespace std;
void setup()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
}
struct DSU
{
int par[100000], sz[100000];
inline DSU()
{
for (int i = 0; i < 1e5; ++i)
{
par[i] = i;
sz[i] = 1;
}
}
inline int Get(int inp)
{
return (inp == par[inp] ? inp : par[inp] = Get(par[inp]));
}
inline bool Combine(int ina, int inb)
{
ina = Get(ina);
inb = Get(inb);
if (ina != inb)
{
if (sz[ina] < sz[inb])
{
swap(ina, inb);
}
sz[ina] += sz[inb];
par[inb] = ina;
return true;
}
return false;
}
} dsu1, dsu2;
int n, m, a, b, c, d = 0;
int head[100000], near[100000];
vector<pair<int, int>> g[100000];
inline void DFS(int node, int last)
{
head[node] = near[node] = a++;
for (auto & i : g[node])
{
if (i.second != last)
{
if (head[i.first] == 0)
{
DFS(i.first, i.second);
if (near[i.first] > head[node])
{
cout << i.first + 1 << " " << node + 1 << "\n";
}
}
near[node] = min(near[node], near[i.first]);
}
}
}
int main()
{
setup();
cin >> n >> m;
while (m--)
{
cin >> a >> b;
a--;
b--;
c = 0;
if (dsu1.Get(a) != dsu1.Get(b))
{
c += dsu1.Combine(a, b);
}
else
{
c += dsu2.Combine(a, b);
}
if (c > 0)
{
g[a].push_back({b, d});
g[b].push_back({a, d++});
}
}
for (int i = 0; i < n; ++i)
{
if (head[i] == 0)
{
a = 1;
DFS(i, -1);
}
}
return 0;
}
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |