#include<bits/stdc++.h>
#define ll long long
#define pii pair<int,int>
#define tiii tuple<int,int,int>
using namespace std;
int LGN = 22;
vector<vector<int>> adj;
vector<int> num, low, scc;
int counter = 0;
int scccounter = 0;
stack<int> S;
vector<char> ans;
void Tarjan(int v, int p){
num[v] = low[v] = counter++;
S.push(v);
for(auto u : adj[v]){
if(u == p) continue;
if(num[u] == -1){
Tarjan(u,v);
low[v] = min(low[v], low[u]);
}else{
low[v] = min(low[v], num[u]);
}
}
if(num[v] == low[v]){
int u;
do{
u = S.top();S.pop();
scc[u] = scccounter;
}while(v != u);
scccounter++;
}
}
// ----
vector<vector<pii>> adjC;
vector<int> depthC;
vector<vector<int>> jumpC;
vector<pii> par;
void DFS(int v, int p, int d){
depthC[v] = d++;
jumpC[0][v] = p;
for(auto u : adjC[v]){
if(u.first == p) continue;
par[u.first] = {v,u.second};
DFS(u.first,v,d+1);
}
}
int lift(int v, int k){
for(int i = 0; i <= LGN; i++){
if(k & (1 << i)){
v = jumpC[i][v];
}
}
return v;
}
int LCA(int a, int b){
if(depthC[b] > depthC[a]) swap(a,b);
a = lift(a, depthC[a]-depthC[b]);
if(a == b) return a;
for(int k = LGN; k>= 0; k--){
if(jumpC[k][a] != jumpC[k][b]){
a = jumpC[k][a];
b = jumpC[k][b];
}
}
return jumpC[0][a];
}
void adjust(int v, int t, bool up){
if(v == t) return;
adjust(par[v].first,t,up);
if(up)ans[par[v].second] = 'L';
else ans[par[v].second] = 'R';
par[v] = par[par[v].first];
}
int main(){
int n,m;
cin >> n >> m;
low = num = scc = vector<int>(n,-1);
adj.resize(n);
vector<pii> edges(m);
for(int i = 0; i < m; i++){
int a,b;
cin >> a >> b;
a--;b--;
edges[i] = {a,b};
adj[a].push_back(b);
adj[b].push_back(a);
}
int p;
cin >> p;
vector<pii> req(p);
ans.resize(m);
for(int i = 0; i < p; i++){
int a,b;
cin >> a >> b;
a--;b--;
req[i] = {a,b};
}
for(int i = 0; i < n; i++){
if(num[i] == -1){
Tarjan(i,i);
}
}
adjC.resize(scccounter);
jumpC.resize(LGN+1, vector<int>(scccounter));
depthC.resize(scccounter);
par.resize(scccounter);
for(int i = 0 ;i < m; i++){
int a,b;
tie(a,b) = edges[i];
if(scc[a] == scc[b]){
ans[i] = 'B';
}else{
adjC[scc[a]].push_back({scc[b],i});
adjC[scc[b]].push_back({scc[a],i});
}
}
for(int k = 1; k <= LGN; k++){
for(int i = 0; i < scccounter; i++){
jumpC[k][i] = jumpC[k-1][jumpC[k-1][i]];
}
}
DFS(0,0,0);
for(int i = 0; i < p; i++){
int a,b;
tie(a,b) = req[i];
if(scc[a] == scc[b]) continue;
int lca = LCA(scc[a],scc[b]);
if(lca == scc[a] || lca == scc[b]){
if(lca == scc[a]) swap(a,b);
adjust(scc[a],lca,true);
}else{
adjust(scc[a],lca,true);
adjust(scc[b],lca,false);
}
}
for(int i = 0; i < m; i++){
int a,b;
tie(a,b) = edges[i];
if(depthC[scc[a]] < depthC[scc[b]]) {
if(ans[i] == 'L') ans[i] = 'R';
else ans[i] = 'L';
}
}
for(int i = 0; i < m; i++){
cout << ans[i];
}
cout << endl;
}
