// UUID: 36e9a7be-c512-45e4-a18a-5e8b77c61962
#include <bits/stdc++.h>
using namespace std;
vector<vector<int>> critNbrs;
vector<vector<int>> nbrs;
vector<bool> vis;
vector<int> tim, l;
int timePtr;
void dfs(int Index, int Parent=-1) {
vis[Index]=true;
tim[Index]=timePtr++;
l[Index]=tim[Index];
bool parFound=false;
for(int i : nbrs[Index]) {
if(i==Parent && !parFound){
parFound=true;
continue;
}
if(vis[i]) l[Index]=min(l[Index], tim[i]);
else{
dfs(i, Index);
l[Index]=min(l[Index], l[i]);
if(tim[Index]<l[i]){
critNbrs[i].push_back(Index);
critNbrs[Index].push_back(i);
}
}
}
}
vector<int> compId;
void GenComps(int Index, int ID){
if(compId[Index]!=-1) return;
compId[Index]=ID;
for(int i : nbrs[Index]){
bool isCutEdge=false;
for(int j : critNbrs[Index]) if(i==j){
isCutEdge=true;
break;
}
if(isCutEdge) continue;
GenComps(i, ID);
}
}
int compN=0;
vector<vector<array<int, 3>>> compNbrs;
void GenCompEdges(int Index){
if(vis[Index]) return;
vis[Index]=true;
for(int i : nbrs[Index]){
if(compId[Index]!=compId[i]){
compNbrs[compId[Index]].push_back({compId[i], Index, i});
}
GenCompEdges(i);
}
}
vector<array<int, 3>> par;
vector<int> timout;
void GenParents(int Index){
if(vis[Index]) return;
vis[Index]=true;
tim[Index]=timePtr++;
for(auto [i, u, v] : compNbrs[Index]){
par[i]={Index, u, v};
GenParents(i);
}
timout[Index]=timePtr++;
}
bool IsAncestor(int A, int B){
return tim[A]<=tim[B] && timout[B]<=timout[A];
}
vector<char> compSol;
void AssignEdges(int A, int B){
while(!IsAncestor(A, B)){
compSol[A]='L';
A=par[A][0];
}
while(A!=B){
compSol[B]='R';
B=par[B][0];
}
}
int main() {
int n, m; cin >> n >> m;
nbrs.resize(n);
map<array<int, 2>, int> edgerev;
for(int i=0;i<m;i++){
int u, v; cin >> u >> v;
nbrs[u-1].push_back(v-1);
edgerev[{u-1, v-1}]=i;
nbrs[v-1].push_back(u-1);
}
vis.resize(n);
tim.resize(n);
l.resize(n);
critNbrs.resize(n);
for(int i=0;i<n;i++) if(!vis[i]) dfs(i);
//for(int u=0;u<n;u++) for(auto v : critNbrs[u]) printf("[%d %d]", u+1, v+1);
compId.resize(n, -1);
compN=0;
for(int i=0;i<n;i++) if(compId[i]==-1) GenComps(i, compN++);
vis.assign(compN, false);
compNbrs.resize(compN);
for(int i=0;i<n;i++) GenCompEdges(i);
//for(int x : compId) printf("%d ", x);
for(int i=0;i<compN;i++){
//printf("\n%d: ", i+1);
//for(auto [j, u, v] : compNbrs[i]) printf(" %d (%d %d)", j+1, u+1, v+1);
}
vis.assign(compN, false);
par.resize(compN);
tim.resize(compN);
timout.resize(compN);
timePtr=0;
GenParents(0);
int p; cin >> p;
compSol.resize(compN, 'B');
for(int i=0;i<p;i++){
int u, v; cin >> u >> v;
AssignEdges(compId[u-1], compId[v-1]);
}
vector<char> sol(m, 'B');
/*for(int i=0;i<compN;i++){
//printf("%c", compSol[i]);
int u=par[i][1], v=par[i][2];
if(0==edgerev.count({u, v})) sol[edgerev[{v, u}]]=(compSol[i]=='L'?'R':'L');
else sol[edgerev[{u, v}]]=compSol[i];
}*/
//printf("\n");
for(char x : sol) cout << x;
}
