#include<bits/stdc++.h>
using namespace std;
#define N 100100
#pragma GCC optimize(2)
#define C cyc.abp
struct unionf{
int par[N];
unionf(){
for(int i=0;i<N;i++)
par[i]=i;
}
int abp(int a){
return (par[a]-a?par[a]=abp(par[a]):a);
}
} cyc,comp;
int par[N],sz[N],dep[N];
set<pair<int,int>>st;
vector<pair<int,int>>adj[N];
int depth=0,times=0;
void repos(int x,int p,int d){
par[x]=p,dep[x]=d;
for(auto[i,j]:adj[x])
if(C(i)-p&&C(i)!=x)
repos(C(i),x,d+1);
depth--;
}
int mergepar(int a){
times++;
int b=par[a];
dep[a]=dep[b];
par[a]=par[b];
if(adj[a].size()<adj[b].size())
swap(a,b);
cyc.par[b]=a;
for(auto[i,j]:adj[b])
if(C(i)-a&&C(i)-b){
adj[a].push_back({i,j});
if(C(i)-par[a])
par[C(i)]=a;
}
adj[b].clear();
return a;
}
int main(){
int n,m;
cin>>n>>m;
for(int i=1;i<=n;i++)
sz[i]=1;
while(m--){
int a,b;
cin>>a>>b;
if(C(a)==C(b))
continue;
if(comp.abp(a)==comp.abp(b)){
int acyc=C(a),bcyc=C(b);
while(acyc-bcyc){
if(dep[acyc]<dep[bcyc])
swap(acyc,bcyc);
acyc=mergepar(acyc),
bcyc=C(bcyc);
}
} else {
int acyc=C(a),bcyc=C(b);
int acomp=comp.abp(a),bcomp=comp.abp(b);
if(sz[acomp]<sz[bcomp]) swap(a,b),
swap(acyc,bcyc),swap(acomp,bcomp);
sz[acomp]+=sz[bcomp];
comp.par[bcomp]=acomp;
repos(bcyc,acyc,dep[acyc]+1);
adj[acyc].push_back({b,a});
adj[bcyc].push_back({a,b});
}
}
for(int i=1;i<=n;i++)if(C(i)==i)
for(auto[j,k]:adj[i]) if(C(j)-i)
st.insert({min(j,k),max(j,k)});
for(auto[i,j]:st)
cout<<i<<' '<<j<<'\n';
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
4700 KB |
Output is correct |
2 |
Correct |
1 ms |
4700 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
5 ms |
4956 KB |
Output is correct |
2 |
Correct |
5 ms |
4956 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
170 ms |
4700 KB |
Output is correct |
2 |
Correct |
155 ms |
4700 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
281 ms |
4956 KB |
Output is correct |
2 |
Correct |
339 ms |
4956 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
469 ms |
5700 KB |
Output is correct |
2 |
Correct |
409 ms |
5968 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
611 ms |
7724 KB |
Output is correct |
2 |
Correct |
556 ms |
7768 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
974 ms |
8136 KB |
Output is correct |
2 |
Correct |
1012 ms |
8136 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1268 ms |
8904 KB |
Output is correct |
2 |
Correct |
1201 ms |
9296 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1564 ms |
9160 KB |
Output is correct |
2 |
Correct |
1585 ms |
9420 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1992 ms |
8632 KB |
Output is correct |
2 |
Correct |
1890 ms |
9056 KB |
Output is correct |