/*
ID: noszaly1
TASK: {TASK}
LANG: C++11
*/
//Noszály Áron 10o Debreceni Fazekas Mihály Gimnázium
#include<iostream>
#include<vector>
#include<map>
#include<set>
#include<cassert>
#include<cassert>
#include<unordered_map>
#include<unordered_set>
#include<functional>
#include<queue>
#include<stack>
#include<cstring>
#include<algorithm>
#include<cmath>
#include<sstream>
#include<iomanip>
#include<cstdio>
#include<cstdlib>
#include<numeric>
using namespace std;
#define all(x) (x).begin(), (x).end()
#define pb push_back
#define xx first
#define yy second
#define sz(x) (int)(x).size()
#define gc getchar
#define IO ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0)
#define mp make_pair
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
const double PI=acos(-1);
template<typename T> T getint() {
T val=0;
char c;
bool neg=false;
while((c=gc()) && !(c>='0' && c<='9')) {
neg|=c=='-';
}
do {
val=(val*10)+c-'0';
} while((c=gc()) && (c>='0' && c<='9'));
return val*(neg?-1:1);
}
struct el {
int xx;
bool yy;
int ind;
};
int n,m;
vector<el> adj[100001], cadj[100001];
int b1[100001];
int dfs_ind=0, cind=0, comp[100001];
int dfs_num[100001], dfs_low[100001], par[100001];
map<pair<int,int>, bool> bridge;
void dfs1(int x) {
dfs_num[x]=dfs_low[x]=++dfs_ind;
b1[x]=1;
for(auto i:adj[x]) {
if(par[x]==i.ind) continue ;
if(!b1[i.xx]) {
par[i.xx]=i.ind;
dfs1(i.xx);
if(dfs_low[x]>dfs_low[i.xx]) {
dfs_low[x]=dfs_low[i.xx];
}
if(dfs_low[i.xx]==dfs_num[i.xx]) {
// cerr<<x<<" "<<i.xx<<"\n";
bridge[{x, i.xx}]=true;
bridge[{i.xx, x}]=true;
}
}else {
if(dfs_low[x]>dfs_num[i.xx]) {
dfs_low[x]=dfs_num[i.xx];
}
}
}
//cerr<<x<<" "<<dfs_num[x]<<" "<<dfs_low[x]<<"\n";
b1[x]=2;
}
int b15[100001];
void dfs15(int x) {
b15[x]=1;
comp[x]=cind;
for(auto i:adj[x]) {
if(b15[i.xx]) continue ;
if(bridge[mp(x, i.xx)]) continue ;
dfs15(i.xx);
}
b15[x]=2;
}
int dp[100001][17], b2[100001], lvl[100001];
int up[100001][17];
int down[100001][17];
el parel[100001];
void dfs2(int x) {
b2[x]=1;
for(auto i:cadj[x]) {
if(!b2[i.xx]) {
dp[i.xx][0]=x;
lvl[i.xx]=lvl[x]+1;
parel[i.xx]=i;
dfs2(i.xx);
}
}
b2[x]=1;
}
void calc() {
for(int j=1;j<17;++j) {
for(int i=1;i<=cind;++i) {
if(dp[i][j-1]>0) {
dp[i][j]=dp[dp[i][j-1]][j-1];
}
}
}
}
int lca(int p, int q) {
if(lvl[p]<lvl[q]) swap(p,q);
int i;
for(i=16;i>=0;i--) {
if(dp[p][i]>0 && lvl[p]-lvl[q]>=(1<<i)) {
p=dp[p][i];
}
}
if(p==q) return p;
for(i=16;i>=0;i--) {
if(dp[p][i]>0 && dp[p][i]!=dp[q][i]) {
p=dp[p][i];
q=dp[q][i];
}
}
return dp[p][0];
}
void setUp(int p, int v) {
if(lvl[v]-lvl[p]==0) return ;
for(int i=16;i>=0;i--) {
if(lvl[v]-lvl[p]>=(1<<i)) {
up[v][i]=1;
v=dp[v][i];
}
}
}
void setDown(int p, int v) {
if(lvl[v]-lvl[p]==0) return ;
for(int i=16;i>=0;i--) {
if(lvl[v]-lvl[p]>=(1<<i)) {
down[v][i]=1;
v=dp[v][i];
}
}
}
int main() {
IO;
cin>>n>>m;
for(int i=0;i<m;++i) {
int a,b;
cin>>a>>b;
adj[a].pb({b,false,i});
adj[b].pb({a,true,i});
}
for(int i=1;i<=n;++i) {
if(!b1[i]) dfs1(i);
}
for(int i=1;i<=n;++i) {
if(!b15[i]) {
cind++;
dfs15(i);
}
}
// for(int i=1;i<=n;++i) cerr<<comp[i]<<" ";
// cerr<<"\n";
for(int i=1;i<=n;++i) {
for(auto j:adj[i]) {
if(comp[i]!=comp[j.xx]) {
cadj[comp[i]].pb({comp[j.xx], j.yy, j.ind});
}
}
}
for(int i=1;i<=cind;++i) {
if(!b2[i]) dfs2(i);
}
calc();
int q;
cin>>q;
vector<pair<int,int>> qs(q);
vector<int> ans(m);
for(int i=0;i<q;++i) {
int a,b;
cin>>a>>b;
qs[i]={a,b};
if(comp[a]!=comp[b]) {
int l=lca(comp[a],comp[b]);
// cerr<<l<<" "<<comp[a]<<"up\n";
setUp(l, comp[a]);
// cerr<<l<<" "<<comp[b]<<"down\n";
setDown(l, comp[b]);
}
}
for(int j=16;j>0;j--) {
for(int i=1;i<=cind;++i) {
if(up[i][j]) {
up[i][j-1]=1;
up[dp[i][j-1]][j-1]=1;
}
if(down[i][j]) {
down[i][j-1]=1;
down[dp[i][j-1]][j-1]=1;
}
}
}
for(int i=1;i<=cind;++i) {
if(parel[i].xx==0) continue ;
if(up[parel[i].xx][0]) {
if(parel[i].yy) ans[parel[i].ind]=2;
else ans[parel[i].ind]=1;
}
if(down[parel[i].xx][0]) {
if(parel[i].yy) ans[parel[i].ind]=1;
else ans[parel[i].ind]=2;
}
}
for(int i=0;i<m;++i) {
cout<<"BLR"[ans[i]];
}cout<<"\n";
return 0;
}
