#include <bits/stdc++.h>
#define ll long long
#define pb push_back
#define MASK(x) ((1LL) << (x))
#define BIT(x, i) (((x) >> (i)) & (1LL))
#define str string
#define fi first
#define se second
#define pii pair<int, int>
#define faster ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
#define endline '\n'
#define all(x) (x).begin(),(x).end()
#define log 20
#define FOR(i,l,r,val) for(int i = l;i <= r ; i = i + val)
#define FORD(i,l,r,val) for(int i = l;i >= r; i = i - val)
template<typename T> bool maximize(T &res, const T &val) { if (res < val){ res = val; return 1; }; return 0; }
template<typename T> bool minimize(T &res, const T &val) { if (res > val){ res = val; return 1; }; return 0; }
using namespace std;
int n, m, p;
vector<pii> edges, must_pairs;
bool check_direction(int fixed_edge, int dir) {
// dir = 0: edges[fixed_edge] = a->b
// dir = 1: edges[fixed_edge] = b->a
vector<vector<int>> g(n + 1);
FOR(i, 0, m - 1, 1) {
int u = edges[i].fi;
int v = edges[i].se;
if (i == fixed_edge) {
if (dir == 0) g[u].pb(v);
else g[v].pb(u);
} else {
g[u].pb(v);
g[v].pb(u);
}
}
for (auto [x, y] : must_pairs) {
vector<int> vis(n + 1, 0);
queue<int> q;
q.push(x);
vis[x] = 1;
bool ok = false;
while (!q.empty()) {
int u = q.front(); q.pop();
if (u == y) { ok = true; break; }
for (int nxt : g[u]) {
if (!vis[nxt]) {
vis[nxt] = 1;
q.push(nxt);
}
}
}
if (!ok) return false;
}
return true;
}
int main() {
faster
cin >> n >> m;
edges.resize(m);
FOR(i, 0, m - 1, 1) cin >> edges[i].fi >> edges[i].se;
cin >> p;
must_pairs.resize(p);
FOR(i, 0, p - 1, 1) cin >> must_pairs[i].fi >> must_pairs[i].se;
str ans = "";
FOR(i, 0, m - 1, 1) {
bool okR = check_direction(i, 0);
bool okL = check_direction(i, 1);
if (okR && okL) ans += 'B';
else if (okR) ans += 'R';
else ans += 'L';
}
cout << ans << endline;
}
