#include<bits/stdc++.h>
using namespace std;
using ll = long long;
const int N = 1e5 + 5;
vector<pair<int, int>> adj[N], tree[N];
vector<int> bridge;
pair<int, int> edges[N];
int n, m, q;
vector<int> st;
int in[N], low[N], idx[N], id = 0, t = 0;
void dfs(int u, int pe = -1) {
in[u] = low[u] = ++t;
st.emplace_back(u);
for (auto& p : adj[u]) {
int v, e; tie(v, e) = p;
if (idx[v] || e == pe) continue;
if (!in[v]) {
dfs(v, e);
low[u] = min(low[u], low[v]);
if (low[v] > in[u]) bridge.emplace_back(e);
} else {
low[u] = min(low[u], in[v]);
}
}
if (low[u] == in[u]) {
idx[u] = ++id;
while (!st.empty()) {
int v = st.back(); st.pop_back();
idx[v] = idx[u];
if (v == u) break;
}
}
}
int dep[N], par[N][20];
void dfs2(int u, int p = 0) {
dep[u] = dep[p] + 1;
par[u][0] = p;
for (int i = 1; i < 20; ++i)
par[u][i] = par[par[u][i - 1]][i - 1];
for (auto& pi : tree[u]) {
int v, e; tie(v, e) = pi;
if (v == p) continue;
dfs2(v, u);
}
}
int lca(int u, int v) {
if (dep[u] <= dep[v]) swap(u, v);
for (int i = 19; ~i; --i) if (dep[par[u][i]] >= dep[v]) u = par[u][i];
if (u == v) return u;
for (int i = 19; ~i; --i) if (par[u][i] != par[v][i])
u = par[u][i], v = par[v][i];
return par[u][0];
}
int dir[N][20];
int ans[N];
int main() {
cin.tie(0)->sync_with_stdio(0); cout.tie(0);
cin >> n >> m;
for (int i = 0, u, v; i < m; ++i) {
cin >> u >> v;
adj[u].emplace_back(v, i);
adj[v].emplace_back(u, i);
edges[i] = {u, v};
}
for (int i = 1; i <= n; ++i)
if (!in[i]) dfs(i);
for (auto& i : bridge) {
int u, v; tie(u, v) = edges[i];
u = idx[u], v = idx[v];
tree[u].emplace_back(v, i);
tree[v].emplace_back(u, i);
}
for (int i = 1; i <= n; ++i) {
sort(tree[i].begin(), tree[i].end());
tree[i].erase(unique(tree[i].begin(), tree[i].end()), tree[i].end());
}
dep[0] = -1;
for (int i = 1; i <= id; ++i)
if (!par[i][0]) dfs2(i);
cin >> q;
for (int i = 0, u, v; i < q; ++i) {
cin >> u >> v;
u = idx[u]; v = idx[v];
int z = lca(u, v);
for (int i = 19; ~i; --i) {
if (dep[par[u][i]] >= dep[z])
dir[u][i] = 1, u = par[u][i];
if (dep[par[v][i]] >= dep[z])
dir[v][i] = 2, v = par[v][i];
}
}
for (int i = 19; ~i; --i) {
for (int u = 1; u <= id; ++u) if (dir[u][i]) {
dir[u][i - 1] = dir[u][i];
dir[par[u][i - 1]][i - 1] = dir[u][i];
}
}
for (auto& i : bridge) {
int u, v; tie(u, v) = edges[i];
u = idx[u], v = idx[v];
if (dep[u] > dep[v]) {
ans[i] = dir[u][0];
} else {
if (dir[v][0] == 0) continue;
ans[i] = 3 - dir[v][0];
}
}
for (int i = 0; i < m; ++i) {
if (!ans[i]) cout << 'B';
else if (ans[i] == 1) cout << 'R';
else cout << 'L';
}
return 0;
}
