#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using pii = pair<int, int>;
#define rep(i, n) for (int (i) = 0; (i) < (n); ++(i))
#define all(x) (x).begin(), (x).end()
#define FAST_IO ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
struct edge {
int u, v, id;
};
const int MAXN = 1e5 + 5;
int n, m;
vector<edge> e;
vector<int> g[MAXN];
int tt = 0;
int tin[MAXN];
int fup[MAXN];
bool used[MAXN];
int dsu[MAXN];
int sz[MAXN];
void init() {
rep(i, n) {
dsu[i] = i;
sz[i] = 1;
}
}
int get(int v) {
if (dsu[v] == v) return v;
return (dsu[v] = get(dsu[v]));
}
void merge(int u, int v) {
u = get(u);
v = get(v);
if (u == v) return;
if (sz[u] < sz[v]) swap(u, v);
dsu[v] = u;
sz[u] += sz[v];
}
void dfs(int v, int p) {
tin[v] = fup[v] = tt++;
used[v] = true;
for (auto to : g[v]) {
if (to == p) {
p = -1;
continue;
}
if (used[to]) {
fup[v] = min(fup[v], tin[to]);
} else {
dfs(to, v);
if (fup[to] > tin[v]) {
// bridge
// cout << v << ' ' << to << endl;
} else {
fup[v] = min(fup[v], fup[to]);
merge(v, to);
}
}
}
}
int p[MAXN];
int h[MAXN];
int tout[MAXN];
int up[MAXN][20];
void pre(int v) {
used[v] = true;
if (p[v] == -1) up[v][0] = v;
else up[v][0] = p[v];
for (int i = 1; i < 20; ++i) {
up[v][i] = up[up[v][i - 1]][i - 1];
}
tin[v] = tt++;
for (auto to : g[v]) {
g[to].erase(find(all(g[to]), v));
p[to] = v;
h[to] = h[v] + 1;
pre(to);
}
tout[v] = tt++;
}
int lca(int u, int v) {
if (tin[u] <= tin[v] && tin[v] < tout[u]) return u;
for (int i = 19; i >= 0; --i) {
if (!(tin[up[u][i]] <= tin[v] && tin[v] < tout[up[u][i]])) {
u = up[u][i];
}
}
return p[u];
}
int eup[MAXN];
int edown[MAXN];
void post(int v) {
used[v] = true;
for (auto to : g[v]) {
post(to);
eup[v] = max(eup[v], eup[to] - 1);
edown[v] = max(edown[v], edown[to] - 1);
}
}
int main() {
FAST_IO;
cin >> n >> m;
rep(i, m) {
int u, v;
cin >> u >> v;
u--; v--;
g[u].push_back(v);
g[v].push_back(u);
e.push_back({u, v, i});
}
init();
rep(i, n) {
if (!used[i]) {
dfs(i, -1);
}
}
rep(i, n) {
g[i].clear();
}
map<int, int> cc;
rep(i, n) {
dsu[i] = get(i);
}
rep(i, n) {
if (cc.find(dsu[i]) == cc.end()) {
int id = cc.size();
cc[dsu[i]] = id;
}
dsu[i] = cc[dsu[i]];
}
// rep(i, n) {
// cout << dsu[i] << ' ';
// }
// cout << endl;
// return 0;
rep(i, m) {
int &u = e[i].u, &v = e[i].v;
u = dsu[u]; v = dsu[v];
// cout << u << ' ' << v << endl;
if (u == v) continue;
g[u].push_back(v);
g[v].push_back(u);
}
tt = 0;
p[0] = -1;
fill(used, used + cc.size(), false);
vector<int> roots;
rep(i, cc.size()) {
if (!used[i]) {
pre(i);
roots.push_back(i);
}
}
// pre(0);
// return 0;
int k;
cin >> k;
rep(i, k) {
int u, v;
cin >> u >> v;
u--; v--;
u = dsu[u];
v = dsu[v];
if (u == v) continue;
int lc = lca(u, v);
if (u != lc) {
eup[u] = max(eup[u], h[u] - h[lc]);
}
if (v != lc) {
edown[v] = max(edown[v], h[v] - h[lc]);
}
}
for (auto v : roots) {
post(v);
}
rep(i, m) {
int u = e[i].u, v = e[i].v;
if (u == v) {
cout << 'B';
continue;
}
bool sw = false;
if (p[v] == u) {
sw = true;
swap(u, v);
}
// p[u] == v
if (!edown[u] && !eup[u]) {
cout << 'B';
continue;
}
if (edown[u]) {
sw ^= 1;
}
cout << "RL"[sw];
}
cout << endl;
}
