#include <bits/stdc++.h>
using namespace std;
int const MAX=1e5+5;
int const LOG=20;
int n,m;
struct edge{
int u,v;
}edges[MAX];
struct muchie{
int vec,id;
};
vector<muchie>tree[MAX];
int h[MAX],low[MAX];
vector<int>critical_edges;
bool viz[MAX];
stack<int>stv;
int grp[MAX];
int total_nodes;
vector<muchie>comp_tree[MAX];
int lift[MAX][LOG];
int up[MAX],down[MAX];
char ans[MAX];
void read(){
cin>>n>>m;
int i;
for(i=1;i<=m;++i){
int u,v;
cin>>u>>v;
edges[i]={u,v};
tree[u].push_back({v,i});
tree[v].push_back({u,i});
}
}
void minself(int& x,int val){
if(x>val)
x=val;
}
void dfs_biconex(int nod,int id_p){
viz[nod]=1;
low[nod]=h[nod];
stv.push(nod);
for(auto [vec,id] : tree[nod])
if(id!=id_p){
if(viz[vec])
minself(low[nod],h[vec]);
else{
h[vec]=h[nod]+1;
dfs_biconex(vec,id);
minself(low[nod],low[vec]);
}
}
if(low[nod]==h[nod]){
if(id_p)
critical_edges.push_back(id_p);
++total_nodes;
while(stv.top()!=nod){
grp[stv.top()]=total_nodes;
stv.pop();
}
grp[nod]=total_nodes;
stv.pop();
}
}
void start_dfs_biconex(){
int i;
for(i=1;i<=n;++i)
if(!viz[i])
dfs_biconex(i,0);
for(i=1;i<=n;++i){
viz[i]=0;
h[i]=0;
}
}
void insert_edges(){
for(auto id : critical_edges){
auto [u,v] = edges[id];
u=grp[u];
v=grp[v];
comp_tree[u].push_back({v,id});
comp_tree[v].push_back({u,id});
}
}
void dfs_init(int nod){
viz[nod]=1;
int i;
for(i=1;i<LOG;++i)
lift[nod][i]=lift[lift[nod][i-1]][i-1];
for(auto [fiu,id] : comp_tree[nod])
if(fiu!=lift[nod][0]){
lift[fiu][0]=nod;
h[fiu]=h[nod]+1;
dfs_init(fiu);
}
}
void start_dfs_init(){
int i;
for(i=1;i<=total_nodes;++i)
if(!viz[i])
dfs_init(i);
for(i=1;i<=total_nodes;++i)
viz[i]=0;
}
int lca(int u,int v){
if(h[u]<h[v])
swap(u,v);
int dif=h[u]-h[v];
int i;
for(i=0;i<LOG;++i)
if(dif&(1<<i))
u=lift[u][i];
if(u==v)
return u;
for(i=LOG-1;i>=0;--i)
if(lift[u][i]!=lift[v][i]){
u=lift[u][i];
v=lift[v][i];
}
return lift[u][0];
}
void process_queries(){
int q;
cin>>q;
int i;
for(i=1;i<=q;++i){
int u,v;
cin>>u>>v;
u=grp[u];
v=grp[v];
if(u!=v){
int lc=lca(u,v);
++up[u];
--up[lc];
++down[v];
--down[lc];
}
}
}
void dfs_solve(int nod,int id_p){
viz[nod]=1;
for(auto [fiu,id] : comp_tree[nod])
if(fiu!=lift[nod][0]){
dfs_solve(fiu,id);
up[nod]+=up[fiu];
down[nod]+=down[fiu];
}
if(up[nod]){
if(grp[edges[id_p].u]==nod)
ans[id_p]='R';
else
ans[id_p]='L';
}
if(down[nod]){
if(grp[edges[id_p].u]==nod)
ans[id_p]='L';
else
ans[id_p]='R';
}
}
void start_dfs_solve(){
int i;
for(i=1;i<=total_nodes;++i)
if(!viz[i])
dfs_solve(i,0);
for(i=1;i<=total_nodes;++i)
viz[i]=0;
}
void write(){
int i;
for(i=1;i<=m;++i){
if(!ans[i])
ans[i]='B';
cout<<ans[i];
}
}
int main()
{
read();
start_dfs_biconex();
insert_edges();
start_dfs_init();
process_queries();
start_dfs_solve();
write();
return 0;
}
