#include <bits/stdc++.h>
using namespace std;
const int N = 1e6+5;
int n, m;
vector<pair<int,int>> gr[N];
int lvl[N], up[N], P[N][20];
int in[N], out[N];
int timer;
int A[N], B[N];
void dfs(int x, int ind, int p) {
lvl[x] = lvl[p] + 1;
P[x][0] = p;
for (int i = 1; i < 20; i++) {
P[x][i] = P[P[x][i-1]][i-1];
}
in[x] = timer++;
for (auto [to, i] : gr[x]) {
if (lvl[to] == 0) {
dfs(to, i, x);
up[x] += up[to];
} else {
if (i == ind) continue;
if (lvl[to] < lvl[x]) {
up[x]++;
} else {
up[x]--;
}
}
}
out[x] = timer;
}
bool check(int x, int y) {
return in[x] <= in[y] && out[y] <= out[x];
}
int lca(int x, int y) {
if (check(x, y)) return x;
for (int i = 19; i >= 0; i--) {
if (P[x][i] && !check(P[x][i], y)) {
x = P[x][i];
}
}
return P[x][0];
}
pair<int,int> edge[N];
int fix[N];
char answer[N];
void dfs1(int x, int ind) {
fix[x] = 1;
for (auto [to, i] : gr[x]) {
if (fix[to]) continue;
dfs1(to, i);
A[x] += A[to];
B[x] += B[to];
}
if (up[x] == 0 && ind != -1) {
if (A[x] > 0) {
if (edge[ind] == make_pair(x, P[x][0])) {
answer[ind] = 'R';
} else {
answer[ind] = 'L';
}
} else if (B[x] > 0){
if(edge[ind] == make_pair(x, P[x][0])) {
answer[ind] = 'L';
} else {
answer[ind] = 'R';
}
}
}
}
int main() {
cin >> n >> m;
for (int i = 0; i < m; i++) {
int x, y;
cin >> x >> y;
gr[x].push_back({y, i});
gr[y].push_back({x, i});
edge[i] = {x, y};
answer[i] = 'B';
}
for (int i = 1; i <= n; i++) {
if (lvl[i]) continue;
dfs(i, -1, 0);
}
int k;
cin >> k;
while (k--) {
int x, y;
cin >> x >> y;
int z = lca(x, y);
A[x]++; A[z]--;
B[y]++; B[z]--;
}
for (int i = 1; i <= n; i++) {
if (fix[i]) continue;
dfs1(i, -1);
}
for (int i = 0; i < m; i++) {
cout << answer[i];
}
}
