#include<bits/stdc++.h>
using namespace std;
#define FOR(i,a,b) for(int i=(a); i<=(b); ++i)
#define FORD(i,a,b) for(int i=(a); i>=(b); --i)
#define sz(a) (int)(a).size()
#define all(a) (a).begin(),(a).end()
#define ii pair<int,int>
#define fi first
#define se second
#define eb emplace_back
#define pb push_back
#define ll long long
const int N=1e5+5;
int n,m,p,num[N],low[N],tin[N],tout[N],ans[N],par[N],parid[N],up[N][20],h[N],Time;
ii edge[N];
struct HalfEdge{
int v,id;
};
struct DSU{
int par[N];
int find(int a){
return par[a]==0?a:par[a]=find(par[a]);
}
void unite(int a, int b){
a=find(a); b=find(b);
if(a!=b){
par[b]=a;
}
}
} dsu,dsu2;
vector<HalfEdge> adj[N],tree[N];
void dfs(int u, int lid){
num[u]=low[u]=++Time;
for(HalfEdge he:adj[u]) if(he.id!=lid){
if(!num[he.v]){
dfs(he.v,he.id);
low[u]=min(low[u],low[he.v]);
if(low[he.v]<num[he.v]) dsu.unite(u,he.v);
}
else{
low[u]=min(low[u],num[he.v]);
}
}
}
void dfsTree(int u, int lid){
tin[u]=++Time;
for(HalfEdge he:tree[u]) if(he.id!=lid){
par[he.v]=u;
parid[he.v]=he.id;
up[he.v][0]=u;
FOR(i,1,17){
up[he.v][i]=up[up[he.v][i-1]][i-1];
}
h[he.v]=h[u]+1;
dfsTree(he.v,he.id);
}
tout[u]=Time;
}
bool chkSub(int r, int u){
return tin[r]<=tin[u]&&tout[u]<=tout[r];
}
int lca(int u, int v){
if(h[u]<h[v]) swap(u,v);
int d=h[u]-h[v];
FOR(i,0,17) if(d>>i&1) u=up[u][i];
if(u==v) return u;
FORD(i,17,0){
if(up[u][i]!=up[v][i]){
u=up[u][i];
v=up[v][i];
}
}
return up[u][0];
}
void solve(){
cin>>n>>m;
FOR(i,1,m){
int a,b; cin>>a>>b;
edge[i]={a,b};
adj[a].pb({b,i});
adj[b].pb({a,i});
}
FOR(i,1,n) if(!num[i]) dfs(i,0);
FOR(u,1,n){
for(HalfEdge he:adj[u]){
if(dsu.find(u)!=dsu.find(he.v)){
tree[dsu.find(u)].pb({dsu.find(he.v),he.id});
}
}
}
Time=0;
FOR(i,1,n) if(!tin[i]) dfsTree(i,0);
memset(ans,-1,sizeof(ans));
cin>>p;
FOR(i,1,p){
int x,y; cin>>x>>y;
x=dsu.find(x);
y=dsu.find(y);
if(x==y) continue;
int l=lca(x,y);
while(h[x]>h[l]){
if(dsu.find(edge[parid[x]].fi)==x){
ans[parid[x]]=0;
}
else{
ans[parid[x]]=1;
}
// x=par[x];
dsu2.unite(par[x],x);
x=dsu2.find(par[x]);
}
while(h[y]>h[l]){
if(dsu.find(edge[parid[y]].se)==y){
ans[parid[y]]=0;
}
else{
ans[parid[y]]=1;
}
// y=par[y];
dsu2.unite(par[y],y);
y=dsu2.find(par[y]);
}
}
FOR(i,1,m){
if(ans[i]==0) cout<<'R';
else if(ans[i]==1) cout<<'L';
else cout<<'B';
}
}
int32_t main(){
#define task "oneway"
if(fopen(task".inp","r")){
freopen(task".inp","r",stdin);
freopen(task".out","w",stdout);
}
cin.tie(0)->sync_with_stdio(0);
int tc=1; //cin>>tc;
FOR(i,1,tc){
solve();
}
}
