#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define f(i,a,b) for(int i = a; i < b; i++)
#define fa(i,a,b) for(int i = a; i >= b; i--)
const int N = 1e5 + 5;
int n, m, q;
int U[N], V[N], col, color[N], direction[N], sum[N];
bool is_bridge[N];
int tin[N], tim, low[N], pa[N];
vector <int> adj[N], curr;
void dfs(int u, int f){
tin[u] = low[u] = ++tim;
curr.push_back(u);
pa[u] = f;
int r = 0;
for(int v: adj[u]){
if(v == f) {r++; continue; }
if(tin[v] == 0){
dfs(v, u);
low[u] = min(low[u], low[v]);
}
else low[u] = min(low[u], tin[v]);
}
if(low[u] == tin[u] and r <= 1) {
col++;
while(!curr.empty()){
int w = curr.back();
color[w] = col;
curr.pop_back();
if(w == u) break;
}
if(f != 0)
is_bridge[u] = 1;
}
}
void DFS(int u, int f){
tin[u] = ++tim;
for(int v: adj[u]){
if(v == f) continue;
if(tin[v] == 0){
DFS(v, u);
sum[u] += sum[v];
}
}
}
int main(){
cin >> n >> m;
f(i,0,m){
cin >> U[i] >> V[i];
if(U[i] != V[i])
adj[U[i]].push_back(V[i]), adj[V[i]].push_back(U[i]);
}
f(i,1,n+1) if(tin[i] == 0) dfs(i, 0);
cin >> q;
f(i,0,q){
int u, v;
cin >> u >> v;
if(color[u] != color[v]) sum[u]++, sum[v]--;
}
tim = 0;
f(i,1,n+1) tin[i] = 0;
f(i,1,n+1) if(tin[i] == 0) DFS(i, 0);
f(i,1,n+1) if(is_bridge[i] and sum[i] != 0) direction[i] = sum[i]/abs(sum[i]);
f(i,0,m){
if((pa[U[i]] == V[i] and direction[U[i]] == 1) or (pa[V[i]] == U[i] and direction[V[i]] == -1)) cout << 'R';
else if((pa[U[i]] == V[i] and direction[U[i]] == -1) or (pa[V[i]] == U[i] and direction[V[i]] == 1)) cout << 'L';
else cout << 'B';
}
cout << "\n";
return 0;
}
