#include<bits/stdc++.h>
using namespace std;
#define all(x) x.begin(),x.end()
int n,m;
vector<int> a,b;
vector<int> low,in;
vector<vector<int>> adj;
vector<int> ab,br;
vector<int> num;
vector<int> bcc;
vector<int> st;
vector<int> dx;
vector<int> dis;
int timet=1,bcc_cnt=0;
void dfs1(int k,int pa){
in[k]=low[k]=timet++;
st.push_back(k);
for(int i:adj[k]){
int j=ab[i]^k;
if(pa==j){
continue;
}
if(low[j]){
low[k]=min(low[k],in[j]);
}
else{
dfs1(j,k);
low[k]=min(low[k],low[j]);
if(low[j]==in[j]){
br[i]=1;
}
}
}
if(low[k]==in[k]){
bcc_cnt++;
while(st.back()!=k){
bcc[st.back()]=bcc_cnt;
st.pop_back();
}
st.pop_back();
bcc[k]=bcc_cnt;
}
}
void dfs2(int k){
for(int j:adj[k]){
if(dis[j]){
continue;
}
dis[j]=dis[k]+1;
dfs2(j);
dx[k]+=dx[j];
}
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(0);
cin>>n>>m;
adj.resize(n);
in.resize(n);
low.resize(n);
ab.resize(m);
br.resize(m);
a.resize(m);
b.resize(m);
bcc.resize(n);
for(int i=0;i<m;i++){
cin>>a[i]>>b[i];a[i]--;b[i]--;
adj[a[i]].push_back(i);
adj[b[i]].push_back(i);
ab[i]=a[i]^b[i];
}
dfs1(0,-1);
for(int i=0;i<m;i++){
a[i]=bcc[a[i]];
b[i]=bcc[b[i]];
}
adj.clear();
adj.resize(bcc_cnt+1);
dis.resize(bcc_cnt+1);
dx.resize(bcc_cnt+1);
for(int i=0;i<m;i++){
adj[a[i]].push_back(b[i]);
adj[b[i]].push_back(a[i]);
}
int q;cin>>q;
for(int i=0;i<q;i++){
int c,d;cin>>c>>d;c--;d--;
c=bcc[c],d=bcc[d];
dx[c]++;
dx[d]--;
}
dis[1]=1;
dfs2(1);
for(int i=0;i<m;i++){
if(!br[i]){
cout<<'B';
}
else{
if(dis[a[i]]>dis[b[i]]){
if(dx[a[i]]==0){
cout<<'B';
}
else if(dx[a[i]]>0){
cout<<'R';
}
else{
cout<<'L';
}
}
else{
if(dx[b[i]]==0){
cout<<'B';
}
else if(dx[b[i]]>0){
cout<<'L';
}
else{
cout<<'R';
}
}
}
}
return 0;
}
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
1 ms |
212 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
1 ms |
212 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
1 ms |
212 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
