/* In the name of God */
#include <iostream>
#include <iomanip>
#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include <string>
#include <string.h>
#include <algorithm>
#include <bitset>
#include <vector>
#include <stack>
#include <queue>
#include <set>
#include <list>
#include <map>
#include <numeric>
#include <limits>
#include <limits.h>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> PII;
typedef pair<ll, ll> PLL;
typedef map<int, int> MPII;
typedef vector<int> VI;
typedef vector<ll> VL;
#define PB push_back
#define POP pop_back
#define MP make_pair
#define all(a) (a).begin(), (a).end()
#define SORT(a) sort(all(a))
#define REVERSE(a) reverse(all(a))
#define sep ' '
#define endl '\n'
#define dbg(x) cerr << '[' << #x << ": " << x << "]\n"
#define dbg2(x, y) cerr << '[' << #x << ": " << x << ", " << #y << ": " << y << "]\n"
#define Yes cout << "Yes\n"
#define YES cout << "YES\n"
#define No cout << "No\n"
#define NO cout << "NO\n"
#define OK cout << "OK\n"
const ll INF = (ll)2e18 + 1386;
const ld eps = 0.000000000000001;
const int MOD = 1e9 + 7;
inline int mod_add(int a, int b){ int res = a + b; return (res >= MOD? res - MOD : res); }
inline int mod_neg(int a, int b){ int res = (abs(a - b) < MOD? a - b : (a - b) % MOD); return (res < 0? res + MOD : res); }
inline int mod_mlt(int a, int b){ return (1ll * a * b % MOD); }
inline string intToString(ll a){ char x[100]; sprintf(x, "%lld", a); string s = x; return s; }
inline ll stringToInt(string s){ ll res; char x[100]; strcpy(x, s.c_str()); sscanf(x, "%lld", &res); return res; }
inline void fileIO(string i, string o){ freopen(i.c_str(), "r", stdin); freopen(o.c_str(), "w", stdout); }
const int MAXN = 2e5 + 5, LOG = 23;
int n, m, q, par[MAXN][LOG], h[MAXN], psU[MAXN], psD[MAXN], st[MAXN], mnback[MAXN], timer, ans[MAXN], jahat[MAXN];
bool boreshi[MAXN], mark[MAXN], mark2[MAXN];
vector<PII> N[MAXN];
void dfs(int v, int lst, int height){
mark[v] = 1;
h[v] = height++;
mnback[v] = st[v] = timer++;
for (auto [u, e] : N[v]){
if (!mark[u]){
par[u][0] = v;
for (int i = 1; i < LOG; i++){
par[u][i] = par[par[u][i - 1]][i - 1];
}
dfs(u, e, height);
if (mnback[u] > st[v]) boreshi[e] = 1;
mnback[v] = min(mnback[v], mnback[u]);
}
else if (e != lst){
mnback[v] = min(mnback[v], st[u]);
}
}
}
int balaaaaaa(int v, int k){
for (int i = LOG - 1; i >= 0; i--){
if (k >> i & 1){
v = par[v][i];
}
}
return v;
}
int LCA(int u, int v){
if (h[u] > h[v]) swap(u, v);
v = balaaaaaa(v, h[v] - h[u]);
if (u == v) return v;
for (int i = LOG - 1; i >= 0; i--){
if (par[v][i] != par[u][i]){
v = par[v][i], u = par[u][i];
}
}
return par[u][0];
}
void dfs_ans(int v){
mark2[v] = 1;
for (auto [u, e] : N[v]){
if (!mark2[u]){
dfs_ans(u);
psD[v] += psD[u], psU[v] += psU[u];
if (boreshi[e] && (psD[u] || psU[u])){
if ((jahat[e] == v && psD[u]) || (jahat[e] == u && psU[u])) ans[e] = 1;
else ans[e] = 2;
}
else ans[e] = 3;
}
}
}
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
cin >> n >> m;
for (int i = 1; i <= m; i++){
int x, y; cin >> x >> y;
N[x].PB({y, i}), N[y].PB({x, i});
jahat[i] = x;
}
for (int i = 1; i <= n; i++){
if (!mark2[i]){
dfs_ans(i);
for (int j = 0; j < LOG; j++){
par[i][j] = i;
}
dfs(i, -1, 1);
}
}
cin >> q;
while (q--){
int u, v; cin >> u >> v;
int lca = LCA(u, v);
psU[u]++, psU[lca]--;
psD[v]++, psD[lca]--;
}
fill(mark2, mark2 + MAXN, 0);
for (int i = 1; i <= n; i++){
if (!mark2[i]){
dfs_ans(i);
}
}
for (int i = 1; i <= m; i++){
if (ans[i] == 1) cout << 'R';
else if (ans[i] == 2) cout << 'L';
else cout << 'B';
}
return 0;
}
