#include<bits/stdc++.h>
#define pi pair<int,int>
#define fi first
#define se second
using namespace std;
const int N=1e5+5;
int n,m,p;
struct node{
int to,num,direct;
};
vector<node>g[N];
vector<pi>edge;
bool vis[N];
int num[N],low[N],tdfs=0;
bool bridge[N],joint[N];
void dfs(int u,int p)
{
low[u]=num[u]=++tdfs;
vis[u]=1;
for (node &e:g[u]) {
int v=e.to,pos=e.num;
if (v==p) continue;
if (!vis[v]) {
dfs(v,u);
low[u]=min(low[u],low[v]);
if (low[v]==num[v]) bridge[pos]=1;
}
else low[u]=min(low[u],num[v]);
}
}
int ans[N];
vector<pi>require;
void dfs2(int u,int p,int stop)
{
vis[u]=1;
if (u==stop) return;
for (node &e:g[u]) {
int v=e.to,pos=e.num;
if (vis[v]) continue;
if (bridge[pos]) {
if (e.direct) ans[pos]=2; else ans[pos]=1;
}
dfs2(v,u,stop);
}
}
int main()
{
cin>>n>>m;
for (int i=1;i<=m;i++) {int a,b; cin>>a>>b; edge.push_back({a,b}); g[a].push_back({b,i,0}); g[b].push_back({a,i,1});}
for (int i=1;i<=n;i++) if (!vis[i]) dfs(i,i);
cin>>p;
for (int i=1;i<=p;i++) {int x,y; cin>>x>>y; require.push_back({x,y});}
for (int i=1;i<=p;i++) {
fill_n(vis,n+1,0);
dfs2(require[i-1].fi,require[i-1].fi,require[i-1].se);
}
for (int i=1;i<=m;i++) if (ans[i]==0) cout<<"B"; else if (ans[i]==1) cout<<"R"; else cout<<"L";
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
3928 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
3928 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
3928 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
