#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#include <bits/stdc++.h>
using namespace std;
#define trav(a, x) for(auto& a : x)
#define FOR(i, a, b) for (int i=(a); i<=(signed)(b); i++)
#define ROF(i, a, b) for (int i=(a); i>=(signed)(b); i--)
#define F0R(i, a) for (int i=0; i<(signed)(a); i++)
#define vi vector<int>
#define f first
#define s second
#define all(v) (v).begin(), (v).end()
typedef long long ll;
const ll mod = 1e9 + 7;
int main()
{
ios_base::sync_with_stdio(0); cin.tie(0);
int n, m; cin >> n >> m;
vector<pair<int, int>> ed(m);
vector<vector<pair<int, int>>> adj(n);
map<pair<int, int>, int> cnt;
F0R(_, m) {
int u, v; cin >> u >> v;
u--; v--;
adj[u].emplace_back(v, _);
adj[v].emplace_back(u, _);
ed[_] = {u, v};
}
vector<int> vis(n);
vector<int> num(n), low(n), bridge(m);
int timer = 0;
auto dfs1 = [&] (auto dfs1, int u, int p = -1)-> void {
vis[u] = 1;
num[u] = low[u] = ++timer;
bool mul_ed = false;
for(auto [v, id] : adj[u]) {
if(v==p && !mul_ed) {
mul_ed = true;
continue;
}
if(vis[v]) {
low[u] = min(low[u], num[v]);
}
else {
dfs1(dfs1, v, u);
low[u] = min(low[u], low[v]);
if(low[v]==num[v]) {
bridge[id] = 1;
// cout << id << "\n";
}
}
}
};
F0R(i, n) if(!vis[i]) dfs1(dfs1, i);
vector<int> d2(n);
int p; cin >> p;
F0R(i, p) {
int u, v; cin >> u >> v;
u--; v--;
d2[u]++;
d2[v]--;
}
// F0R(i, n) cout << d2[i] << " ";
// cout << "\n";
vis = vector<int>(n);
vector<char> ans(m, 'B');
auto dfs2 = [&] (auto dfs2, int u) -> void {
vis[u]=1;
for(auto [v, id] : adj[u]) if(!vis[v]) {
dfs2(dfs2, v);
d2[u] += d2[v];
if(!bridge[id] || !d2[v]) continue;
if(d2[v] > 0 && ed[id].f == u || d2[v] < 0 && ed[id].f == v) ans[id] = 'L';
else ans[id] = 'R';
}
};
F0R(i, n) if(!vis[i]) dfs2(dfs2, i);
// F0R(i, n) cout << d1[i] << " ";
// cout << "\n";
// F0R(i, n) cout << d2[i] << " ";
// cout << "\n";
trav(u, ans) cout << u;
cout << '\n';
return 0;
}
