#include <iostream>
#include <map>
#include <vector>
#include <climits>
#include <stack>
#include <string>
#include <queue>
#include <algorithm>
#include <set>
#include <unordered_set>
#include <unordered_map>
#include <cmath>
#include <cctype>
#include <bitset>
#include <iomanip>
#include <cstring>
#include <numeric>
using namespace std;
#define int long long
#define pb push_back
#define mp make_pair
#define pii pair<int, int>
#define fi first
#define se second
struct trio{
int a, b, c;
};
int counter=0;
vector<vector<trio> > graph;
vector<int> low, disc, ans, in, out, l, r;
vector<set<int> > s;
void dfs(int node, int par, int d){
disc[node]=low[node]=d;
in[node]=++counter;
for (auto [i, j, dir]:graph[node]){
if (j==par)continue;
if (disc[i])low[node]=min(low[node], disc[i]);
else{
dfs(i, j, d+1);
low[node]=min(low[node], low[i]);
if (low[i]>=disc[i]&&!s[i].empty()){
int c=*s[i].begin();
if (in[i]<=in[l[c]]&&out[i]>=out[l[c]])ans[j]=dir;
else ans[j]=(dir==1?2:1);
}
if (s[i].size()>s[node].size())swap(s[i], s[node]);
for (auto a:s[i]){
if (s[node].find(a)==s[node].end())s[node].insert(a);
else s[node].erase(a);
}
}
}
out[node]=counter;
}
int32_t main(){
int n, m, q, a, b;
cin>>n>>m;
graph.resize(n+1);
low.resize(n+1);
disc.resize(n+1, 0);
ans.resize(m, 0);
in.resize(n+1);
out.resize(n+1);
s.resize(n+1);
for (int i=0; i<m; ++i){
cin>>a>>b;
graph[a].pb({b, i, 1});
graph[b].pb({a, i, 2});
}
cin>>q;
l.resize(q);
r.resize(q);
for(int i=0; i<q; ++i){
cin>>a>>b;
if (a==b)continue;
s[a].insert(i);
s[b].insert(i);
l[i]=a, r[i]=b;
}
for (int i=1; i<=n; ++i)if (!disc[i])dfs(i, -1, 1);
for (int i=0; i<m; ++i){
if (!ans[i])cout<<'B';
else if (ans[i]==1)cout<<'L';
else cout<<'R';
}
}
