#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
#include "debug.h"
#else
#define debug(...) 42
#endif
const int N = 1e5 + 5;
int n, m, p;
int low[N], num[N], lab[N], a[N], ind[N];
vector<int> g[N];
vector<array<int, 2>> tr[N];
int timer;
vector<int> st;
void dfs(int u, int p) {
low[u] = num[u] = ++timer;
st.push_back(u);
bool rep = 0;
for (int v : g[u]) {
if (v == p && !rep) {
rep = 1;
continue;
}
if (!low[v]) {
dfs(v, u);
low[u] = min(low[u], low[v]);
} else {
low[u] = min(low[u], num[v]);
}
}
if (low[u] == num[u]) {
while (1) {
int v = st.back(); st.pop_back();
lab[v] = u;
if (v == u) {
break;
}
}
}
}
void DFS(int u, int p) {
for (auto [v, id] : tr[u]) {
if (v ^ p) {
ind[v] = id;
DFS(v, u);
a[u] += a[v];
}
}
}
int main() {
ios::sync_with_stdio(false); cin.tie(nullptr);
cin >> n >> m;
string res(m, 'B');
vector<array<int, 2>> e(m);
for (int i = 0; i < m; ++i) {
int u, v; cin >> u >> v;
e[i] = {u, v};
g[u].push_back(v);
g[v].push_back(u);
}
dfs(1, 1);
for (int i = 0; i < m; ++i) {
auto [u, v] = e[i];
tie(u, v) = tie(lab[u], lab[v]);
if (u ^ v) {
tr[u].push_back({v, -1 - i});
tr[v].push_back({u, i + 1});
}
}
cin >> p;
while (p--) {
int x, y; cin >> x >> y;
++a[lab[x]], --a[lab[y]];
}
DFS(1, 1);
for (int i = 2; i <= n; ++i) {
if (a[i]) {
bool r = (a[i] > 0) ^ (ind[i] < 0);
int id = abs(ind[i]) - 1;
res[id] = r ? 'R' : 'L';
}
}
cout << res;
return 0;
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
6748 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
6748 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
6748 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
