#include <bits/stdc++.h>
using namespace std;
#define int long long
#define ll long long
#define FOR(i, l, r) for (int i = (l); i <= (r); i++)
#define FOD(i, r, l) for (int i = (r); i >= (l); i--)
#define fi first
#define se second
#define pii pair<int, int>
const ll mod = 1e7 + 1203;
const ll MAXN = 1e5 + 5;
const ll oo = 1e18;
const ll base = 320;
int n, m, p, num[MAXN], low[MAXN], cnt, tp[MAXN], tplt, visited[MAXN], up[MAXN][20], h[MAXN], tp2[MAXN];
int len[MAXN], xuong[MAXN];
vector<int> adj[MAXN], adj2[MAXN], adj3[MAXN];
map<pii, int> cau, kq;
pii canh[MAXN];
void dfs(int u, int par)
{
num[u] = low[u] = ++cnt;
for (auto v : adj[u])
{
if (v == par)
continue;
if (!num[v])
{
// cout << u << ' ' << v << ''
dfs(v, u);
low[u] = min(low[u], low[v]);
if (num[v] == low[v])
{
// cout << u << ' ' << v << ' ';
cau[{u, v}] = 0;
cau[{v, u}] = 0;
}
}
else
{
low[u] = min(low[u], num[v]);
}
}
}
void dfs2(int u)
{
visited[u] = 1;
tp[u] = tplt;
for (auto v : adj2[u])
{
if (!visited[v])
{
dfs2(v);
}
}
}
void dfs3(int u)
{
visited[u]=1;
for (auto v : adj3[u])
{
if (v == up[u][0])
continue;
if(visited[v]) continue;
// cout << u << ' ' << v;
h[v] = h[u] + 1;
up[v][0] = u;
FOR(j, 1, 19)
{
up[v][j] = up[up[v][j - 1]][j - 1];
}
dfs3(v);
}
}
int lca(int u, int v)
{
if (h[u] != h[v])
{
if (h[u] < h[v])
{
swap(u, v);
}
int k = h[u] - h[v];
for (int j = 0; (1 << j) <= k; j++)
{
if ((k >> j) & 1)
{
u = up[u][j];
}
}
}
if (u == v)
{
return u;
}
int k = __lg(h[u]);
FOD(j, k, 0)
{
if (up[u][j] != up[v][j])
{
u = up[u][j];
v = up[v][j];
}
}
return up[u][0];
}
int flen[MAXN], fxuong[MAXN];
void dfs4(int u, int par)
{
visited[u] = 1;
flen[u] = len[u];
fxuong[u] = xuong[u];
for (auto v : adj3[u])
{
if (v == par)
continue;
if (!visited[v])
{
// cout << u << ' ' << v << '\n';
dfs4(v, u);
if (flen[v] != 0)
{
if (h[flen[v]] < h[flen[u]])
{
flen[u] = flen[v];
}
kq[{u, v}] = 2;
kq[{v, u}] = 1;
}
if (fxuong[v] != 0)
{
if (h[fxuong[v]] < h[fxuong[u]])
{
fxuong[u] = fxuong[v];
}
kq[{u, v}] = 1;
kq[{v, u}] = 2;
}
}
}
if (flen[u] == u)
{
flen[u] = 0;
}
if (fxuong[u] == u)
{
fxuong[u] = 0;
}
}
signed main()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
if (fopen("oneway.INP", "r"))
{
freopen("oneway.INP", "r", stdin);
freopen("oneway.OUT", "w", stdout);
}
cin >> n >> m;
FOR(i, 1, m)
{
int u, v;
cin >> u >> v;
canh[i] = {u, v};
adj[u].push_back(v);
adj[v].push_back(u);
}
FOR(i, 1, n){
if(!num[i]){
dfs(i, i);
}
}
FOR(i, 1, m)
{
auto [u, v] = canh[i];
if (cau.find({u, v}) == cau.end())
{
// cout << u << ' ' << v << '\n';
adj2[u].push_back(v);
adj2[v].push_back(u);
}
else
{
cau[{u, v}]++;
cau[{v, u}]++;
// cout << u << ' ' << v << '\n';
}
}
FOR(i, 1, n)
{
if (!visited[i])
{
tplt++;
dfs2(i);
}
}
FOR(i, 1, m)
{
auto [u, v] = canh[i];
if (cau.find({u, v}) != cau.end())
{
// cout << u << ' ' << v << '\n';
u = tp[u];
v = tp[v];
adj3[u].push_back(v);
adj3[v].push_back(u);
}
}
memset(visited, 0, sizeof visited);
FOR(i, 1, n){
if(!visited[i])
dfs3(i);
}
// cout << tplt << ' ';
// FOR(i, 1, n)
// {
// cout << tp[i] << ' ';
// }
// cout << '\n';
int p;
cin >> p;
FOR(i, 1, n)
{
len[i] = xuong[i] = i;
}
FOR(i, 1, p)
{
int u, v;
cin >> u >> v;
u = tp[u];
v = tp[v];
int g = lca(u, v);
// cout << u << ' ' << v << ' ' << g << ' ' << '\n';
if (h[g] < h[len[u]])
{
len[u] = g;
}
if (h[g] < h[xuong[v]])
{
xuong[v] = g;
}
}
memset(visited, 0, sizeof visited);
FOR(i, 1, n){
if(!visited[i])
dfs4(i, i);
}
FOR(i, 1, m)
{
auto [u, v] = canh[i];
if (cau.find({u, v}) == cau.end())
{
cout << 'B';
}
else
{
if(cau[{u, v}]>1){
cout << 'B';
continue;
}
// cout << u << ' ' << v << '\n';
u = tp[u];
v = tp[v];
if (kq.find({u, v}) == kq.end())
{
cout << 'B';
}
else if (kq[{u, v}] == 2)
{
cout << 'L';
}
else if (kq[{u, v}] == 1)
{
cout << 'R';
}
// cout << 'R';
}
}
// cout << cau[{4, 1}];
return 0;
}
