#include <bits/stdc++.h>
using namespace std;
#define int long long
#define pi pair<int, int>
#define pii pair<int, pi>
#define fi first
#define se second
#ifdef _WIN32
#define getchar_unlocked _getchar_nolock
#endif
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
int low[200005], dep[200005];
vector <pi> adj[200005];
int brr[200005];
int n, m, q;
set <int> s[200005];
int L[200005], R[200005], S[200005], E[200005];
int huh[200005], cnt = 1;
void dfs(int x, int par, int d){
dep[x] = low[x] = d;
S[x] = cnt++;
bool f = 0;
for(auto [i, j] : adj[x]){
if(j == par)continue;
if(dep[i]){
low[x] = min(low[x], low[i]);
}
else {
dfs(i, j, d + 1);
if(low[i] >= dep[i]){
if(s[i].empty())continue;
int tmp = *s[i].begin();
if(S[i] <= S[L[tmp]] && E[L[tmp]] <= E[i])brr[j] = (huh[j] == i ? 1 : 2);
else brr[j] = (huh[j] == i ? 2 : 1);
}
if(s[x].size() < s[i].size())swap(s[x], s[i]);
for(auto k : s[i]){
if(s[x].find(k) == s[x].end())s[x].insert(k);
else s[x].erase(k);
}
}
}
E[x] = cnt - 1;
}
void solve(){
cin >> n >> m;
for(int i=1;i<=m;i++){
int a, b; cin >> a >> b;
adj[a].push_back({b, i});
adj[b].push_back({a, i});
huh[i] = a;
}
cin >> q;
for(int i=1;i<=q;i++){
int a, b; cin >> a >> b;
s[a].insert(i);
s[b].insert(i);
L[i] = a, R[i] = b;
}
dfs(1, -1, 1);
for(int i=1;i<=m;i++){
if(!brr[i])cout << 'B';
if(brr[i] == 1)cout << 'R';
if(brr[i] == 2)cout << 'L';
}
}
main(){
ios::sync_with_stdio(0);cin.tie(0);
int tc = 1;
//cin >> tc;
for(int tc1=1;tc1<=tc;tc1++){
// cout << "Case #" << tc1 << ": ";
solve();
}
}
Compilation message
oneway.cpp: In function 'void dfs(long long int, long long int, long long int)':
oneway.cpp:25:7: warning: unused variable 'f' [-Wunused-variable]
25 | bool f = 0;
| ^
oneway.cpp: At global scope:
oneway.cpp:72:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
72 | main(){
| ^~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
7 ms |
14420 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
7 ms |
14420 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
7 ms |
14420 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
