// In the name of Allah
#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
#define all(x) (x).begin(),(x).end()
#define len(x) ((ll) (x).size())
#define F first
#define S second
#define pb push_back
#define sep ' '
#define endl '\n'
#define Mp make_pair
#define debug(x) cerr << #x << ": " << x << endl;
#define kill(x) cout << x << '\n', exit(0);
#define set_dec(x) cout << fixed << setprecision(x);
#define file_io(x,y) freopen(x, "r", stdin); freopen(y, "w", stdout);
int n, m;
const int maxn = 1e5 + 5;
int *p, *sz;
int p1[maxn], sz1[maxn];
int p2[maxn], sz2[maxn];
vector<pii> adj[maxn];
vector<pii> ans;
bitset<maxn> mark;
int h[maxn], mn[maxn];
void dfs(int v, int p = -1, int j = -1) {
mark[v] = 1; mn[v] = h[v];
for (auto f : adj[v]) {
int u = f.F, i = f.S;
if (!mark[u]) {
h[u] = h[v] + 1;
dfs(u, v, i);
mn[v] = min(mn[v], mn[u]);
}
else if (i != j) {
mn[v] = min(mn[v], h[u]);
}
}
if (mn[v] >= h[v] && p != -1) {
ans.pb(Mp(min(p, v), max(p, v)));
}
}
int get(int a) {
return ((p[a] == a) ? a : p[a] = get(p[a]));
}
void merge(int a, int b) {
a = get(a); b = get(b);
if (a == b) return ;
if (sz[a] > sz[b]) swap(a, b);
p[a] = b; sz[b] += sz[a]; sz[a] = 0;
}
int main() {
ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
cin >> n >> m;
iota(p1, p1 + n, 0); fill(sz1, sz1 + n, 1);
iota(p2, p2 + n, 0); fill(sz2, sz2 + n, 1);
for (int i = 0; i < m; i++) {
int u, v;
cin >> u >> v; u--; v--;
bool flag = 0;
p = p1; sz = sz1;
if (!flag && get(u) != get(v)) {
flag = 1;
merge(u, v);
adj[u].pb(Mp(v, i)); adj[v].pb(Mp(u, i));
}
p = p2; sz = sz2;
if (!flag && get(u) != get(v)) {
flag = 1;
merge(u, v);
adj[u].pb(Mp(v, i)); adj[v].pb(Mp(u, i));
}
}
for (int i = 0; i < n; i++) {
if (!mark[i]) dfs(i);
}
for (auto f : ans) {
cout << f.F + 1 << sep << f.S + 1 << endl;
}
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
2644 KB |
Output is correct |
2 |
Correct |
1 ms |
2644 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
3284 KB |
Output is correct |
2 |
Correct |
5 ms |
3028 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
84 ms |
3100 KB |
Output is correct |
2 |
Correct |
107 ms |
2960 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
140 ms |
3972 KB |
Output is correct |
2 |
Correct |
184 ms |
3540 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
235 ms |
6008 KB |
Output is correct |
2 |
Correct |
195 ms |
5532 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
334 ms |
12584 KB |
Output is correct |
2 |
Correct |
309 ms |
8996 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
461 ms |
14040 KB |
Output is correct |
2 |
Correct |
469 ms |
10344 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
689 ms |
16724 KB |
Memory limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
823 ms |
16728 KB |
Memory limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
962 ms |
15968 KB |
Output is correct |
2 |
Runtime error |
945 ms |
47476 KB |
Memory limit exceeded |
3 |
Halted |
0 ms |
0 KB |
- |