//Oh? You're Approaching Me?
#include <bits/stdc++.h>
//#include <fstream>
using namespace std;
//
#define int long long
typedef long long ll;
typedef pair<ll, ll> pll;
typedef pair<int, int> pii;
// #pragma GCC optimize("O3,unroll-loops")
#define migmig ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define pb push_back
#define F first
#define S second
#define SZ(x) ll((x).size())
#define all(x) (x).begin(), (x).end()
#define cl clear
#define endl '\n'
#define deb(x) cerr << #x << " = " << x << '\n'
#define dokme(x) {cout << x << endl; return;}
#define wtf cout << "[ahaaaaaaaaaaaaaaaa]" << endl;
const int maxn = 2e5 + 100;
const int mod = 998244353;
const int inf = 1e18 + 5;
const int LOG = 61;
#define mid ((l + r) / 2)
#define lc (id * 2)
#define rc (lc + 1)
//g++ main.cpp -o main && main.exe
int n, m, q, par[maxn], h[maxn], low[maxn];
bool mark[maxn], cut[maxn];
pii E[maxn];
vector<pii> adj[maxn];
vector<pii> G[maxn];
void pre_dfs(int v, int p, int id) {
mark[v] = 1;
h[v] = (p == 0 ? 0 : h[p] + 1);
low[v] = h[v];
for (auto [u, w] : adj[v]) {
if (!mark[u]) {
pre_dfs(u, v, w);
low[v] = min(low[v], low[u]);
}
else if (w != id) {
low[v] = min(low[v], h[u]);
}
}
if (low[v] >= h[v]) {
cut[id] = 1;
// deb(id);
}
}
int get(int v) {
if (v == par[v])
return v;
return par[v] = get(par[v]);
}
void merge(int v, int u) {
v = get(v);
u = get(u);
if (v == u)
return;
par[v] = u;
}
char ans[maxn];
int ps[maxn];
void dfs(int v, int p, int id) {
mark[v] = 1;
for (auto [u, w] : G[v]) {
if (u != p) {
dfs(u, v, w);
ps[v] += ps[u];
}
}
if (ps[v] == 0) {
ans[id] = 'B';
}
else if (ps[v] > 0) {
if (v == E[id].F)
ans[id] = 'R';
else
ans[id] = 'L';
}
else {
if (v == E[id].F)
ans[id] = 'L';
else
ans[id] = 'R';
}
}
signed main() {
cin >> n >> m;
for (int i = 1; i <= m; i++) {
int v, u;
cin >> v >> u;
adj[v].pb({u, i});
adj[u].pb({v, i});
E[i] = {v, u};
}
for (int i = 1; i <= n; i++)
par[i] = i;
pre_dfs(1, 0, 0);
for (int i = 1; i <= m; i++) {
if (!cut[i]) {
merge(E[i].F, E[i].S);
}
}
cin >> q;
while (q--) {
int v, u;
cin >> v >> u;
v = get(v);
u = get(u);
if (v == u)
continue;
ps[v]++;
ps[u]--;
}
for (int i = 1; i <= m; i++) {
int v = get(E[i].F), u = get(E[i].S);
if (v == u) {
ans[i] = 'B';
}
else {
G[v].pb({u, i});
G[u].pb({v, i});
}
}
memset(mark, 0, sizeof mark);
for (int i = 1; i <= n; i++) {
if (!mark[i]) {
dfs(i, 0, 0);
}
}
for (int i = 1; i <= m; i++) {
cout << ans[i];
}
cout << '\n';
}
