// __builtin_popcount(x)
// __builtin_popcountll(x)
#define here cerr<<"===========================================\n"
#include <bits/stdc++.h>
#define ld double
#define ll int
#define ull unsigned long long
#define llinf 100000000000000000LL // 10^17
#define iinf 2000000000 // 2*10^9
#define pb push_back
#define popb pop_back
#define fi first
#define sc second
#define endl '\n'
#define pii pair<int,int>
#define pll pair<ll,ll>
#define pld pair<ld,ld>
#define sz(a) int(a.size())
#define all(a) a.begin(),a.end()
#define ceri(a,l,r) {for(ll i_ = l;i_<=r;i_++) cerr<<a[i_]<< " ";cerr<<endl;}
using namespace std;
#define maxn 100005
ll n,m;
ll dsu[maxn];
ll dsu2[maxn];
vector<ll> g[maxn];
ll low[maxn];
ll in[maxn];
vector<pll> bridge;
bool vis[maxn];
ll root(ll x,ll* dsu){
while(x!=dsu[x]){
dsu[x] = dsu[dsu[x]];
x = dsu[x];
}
return x;
}
void upd(ll x,ll y,ll* dsu){
x = root(x,dsu);
y = root(y,dsu);
dsu[y] = x;
}
bool get(ll x,ll y,ll* dsu){return root(x,dsu)==root(y,dsu);}
ll it = 1;
void dfs(ll u,ll par){
in[u] = low[u] = it++;
vis[u] = 1;
for(ll s : g[u]){
if(s==par) continue;
if(!vis[s]) dfs(s,u);
low[u] = min(low[u],low[s]);
}
if(low[u]>in[par]) bridge.pb({u,par});
}
int main(){
ios_base::sync_with_stdio(false);cerr.tie(0);cout.tie(0);cin.tie(0);
cin >> n >> m;
iota(dsu+1,dsu+n+1,1);
iota(dsu2+1,dsu2+n+1,1);
vector<pll> v;
for(ll i = 1;i<=m;i++){
ll x,y; cin >> x >> y;
if(get(x,y,dsu)){
if(get(x,y,dsu2)) continue;
upd(x,y,dsu2);
}else upd(x,y,dsu);
g[x].pb(y);
g[y].pb(x);
v.pb({x,y});
}
for(ll i = 1;i<=n;i++) if(!vis[i]) dfs(i,i);
for(pll p : bridge) cout<<p.fi<< " "<<p.sc<<endl;
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
2644 KB |
Output is correct |
2 |
Incorrect |
2 ms |
2680 KB |
Wrong number of edges |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
5 ms |
3396 KB |
Output is correct |
2 |
Incorrect |
5 ms |
3156 KB |
Wrong number of edges |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
92 ms |
8560 KB |
Output is correct |
2 |
Incorrect |
101 ms |
8264 KB |
Wrong number of edges |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
140 ms |
13568 KB |
Wrong number of edges |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
289 ms |
21992 KB |
Memory limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
368 ms |
32496 KB |
Memory limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
543 ms |
46324 KB |
Memory limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
751 ms |
59244 KB |
Memory limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
938 ms |
58116 KB |
Memory limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
1162 ms |
65536 KB |
Memory limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |