#include <bits/stdc++.h>
using namespace std;
vector < pair <int , int> > adiacenta[200001] , __adiacenta[200001];
int componenta[200001] , stiva[200001] , moment[200001] , termen[200001];
char rezultat[200001];
inline int Parcurgere (const int nod , const int sursa)
{
bool gasit = false;
stiva[++stiva[0]] = nod;
int minim_accesibil = (moment[nod] = ++moment[0]);
for (auto& vecin : adiacenta[nod]) {
if (vecin.first == sursa && !gasit)
{ gasit = true; continue; }
if (!moment[vecin.first])
{ minim_accesibil = min(minim_accesibil , Parcurgere(vecin.first , nod)); }
else
{ minim_accesibil = min(minim_accesibil , moment[vecin.first]); }
}
if (minim_accesibil == moment[nod])
{
componenta[0]++;
while (true)
{
componenta[stiva[stiva[0]]] = componenta[0];
if (stiva[stiva[0]--] == nod)
{ break; }
}
}
return minim_accesibil;
}
inline void Build (const int nod , const int sursa)
{
for (auto& vecin : __adiacenta[nod]) {
if (vecin.first != sursa)
{
Build(vecin.first , nod);
termen[nod] += termen[vecin.first];
if (termen[vecin.first] <= 0) { rezultat[abs(vecin.second) - 1] = (vecin.second < 0 ? 'L' : 'R'); }
else { rezultat[abs(vecin.second) - 1] = (vecin.second < 0 ? 'R' : 'L'); }
}
}
}
inline void Solve ()
{
int numar_noduri , numar_muchii;
cin >> numar_noduri >> numar_muchii;
for (int indice = 1 ; indice <= numar_muchii ; indice++)
{
int nod[2]; cin >> nod[0] >> nod[1];
adiacenta[nod[0]].emplace_back(nod[1] , indice);
adiacenta[nod[1]].emplace_back(nod[0] , -indice);
}
Parcurgere(1 , 0);
for (int nod = 1 ; nod <= numar_noduri ; nod++) {
for (auto& vecin : adiacenta[nod]) {
if (componenta[nod] == componenta[vecin.first])
{ rezultat[abs(vecin.second) - 1] = 'B'; }
else
{ __adiacenta[componenta[nod]].emplace_back(componenta[vecin.first] , vecin.second); }
}
}
int numar_operatii;
cin >> numar_operatii;
while (numar_operatii--)
{
int nod_1 , nod_2;
cin >> nod_1 >> nod_2;
termen[nod_1]++;
termen[nod_2]--;
}
Build(1 , 0);
cout << rezultat;
}
int main ()
{
ios :: sync_with_stdio(false);
cin.tie(NULL); cout.tie(NULL);
int numar_teste = 1;
// cin >> numar_teste;
while (numar_teste--)
{ Solve(); }
return 0;
}
