#include <bits/stdc++.h>
using namespace std;
// macros
typedef long long ll;
typedef long double ld;
typedef pair<int, int> ii;
typedef pair<ll, ll> lll;
typedef tuple<int, int, int> iii;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef vector<iii> viii;
typedef vector<ll> vll;
typedef vector<lll> vlll;
#define REP(a,b,c) for(int a=int(b); a<int(c); a++)
#define RE(a,c) REP(a,0,c)
#define RE1(a,c) REP(a,1,c+1)
#define REI(a,b,c) REP(a,b,c+1)
#define REV(a,b,c) for(int a=int(c-1); a>=int(b); a--)
#define FOR(a,b) for(auto& a : b)
#define all(a) a.begin(), a.end()
#define INF 1e9
#define EPS 1e-9
#define pb push_back
#define popb pop_back
#define fi first
#define se second
#define sz size()
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
// input
template<class T> void IN(T& x) {cin >> x;}
template<class H, class... T> void IN(H& h, T&... t) {IN(h); IN(t...); }
// output
template<class T1, class T2> void OUT(const pair<T1,T2>& x);
template<class T> void OUT(const T& x) {cout << x;}
template<class H, class... T> void OUT(const H& h, const T&... t) {OUT(h); OUT(t...); }
template<class T1, class T2> void OUT(const pair<T1,T2>& x) {OUT(x.fi,' ',x.se);}
template<class... T> void OUTL(const T&... t) {OUT(t..., "\n"); }
template<class H> void OUTLS(const H& h) {OUTL(h); }
template<class H, class... T> void OUTLS(const H& h, const T&... t) {OUT(h,' '); OUTLS(t...); }
//===================//
// Added libraries //
//===================//
//===================//
//end added libraries//
//===================//
void program();
int main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
program();
}
//===================//
// begin program //
//===================//
const int MX = 2e5;
int n, m, p;
int a[MX], b[MX], x[MX], y[MX];
bitset<MX> visited, inside;
vi adj[MX];
vi dir[MX], rev[MX];
stack<int> stck;
int comp[MX], compN=0;
set<ii> adjComp[MX];
map<ii,int> pToEdge;
char edgeDir[MX];
map<ii,int> cnt;
void dfsDir(int u, int p=-1) {
visited[u] = 1;
inside[u] = 1;
FOR(v,adj[u]) if(v != p) {
if(!visited[v] || inside[v]) {
dir[u].pb(v);
rev[v].pb(u);
}
if(!visited[v]) dfsDir(v, u);
}
inside[u] = 0;
}
void dfsSCC1(int u) {
if(visited[u]) return;
visited[u] = 1;
FOR(v,dir[u]) dfsSCC1(v);
stck.push(u);
}
void dfsSCC2(int u) {
if(visited[u]) return;
visited[u] = 1;
FOR(v,rev[u]) dfsSCC2(v);
comp[u] = compN;
}
void findSCC() {
visited.reset();
dfsSCC1(1);
visited.reset();
while(!stck.empty()) {
int u = stck.top(); stck.pop();
if(visited[u]) continue;
dfsSCC2(u);
compN++;
}
RE1(u,n) {
FOR(v,adj[u]) {
if(comp[u] != comp[v]) {
adjComp[comp[u]].insert({comp[v],pToEdge[{u,v}]});
adjComp[comp[v]].insert({comp[u],pToEdge[{u,v}]});
}
}
}
}
int dfsU;
bool dfs(int u, int t, int p=-1) {
if(u == t) return 1;
FOR(v,adjComp[u]) if(v.fi != p) {
if(dfs(v.fi,t,u)) {
edgeDir[v.se] = (comp[a[v.se]] == u ? 'R' : 'L');
return 1;
}
}
return 0;
}
void program() {
IN(n,m);
RE(i,m) {
int u, v;
IN(u,v);
adj[u].pb(v);
adj[v].pb(u);
a[i] = u;
b[i] = v;
pToEdge[{u,v}] = i;
pToEdge[{v,u}] = i;
cnt[{u,v}]++;
cnt[{v,u}]++;
}
IN(p);
RE(i,p) {
IN(x[i],y[i]);
}
visited.reset();
dfsDir(1);
findSCC();
RE(i,m) edgeDir[i] = 'B';
RE(i,p) dfs(comp[x[i]], comp[y[i]]);
RE(i,m) if(cnt[{a[i],b[i]}] >= 2) edgeDir[i] = 'B';
string ans; ans.assign(m,'X');
RE(i,m) ans[i] = (comp[a[i]] == comp[b[i]] ? 'B' : edgeDir[i]);
OUTL(ans);
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
16 ms |
24064 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
16 ms |
24064 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
16 ms |
24064 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
