/**
* __ __ __ __
* \ \ / / \ \ / (_) _____
* \ \ / /_ _\ \ / / _ ___|_ _|
* \ \/ /| | | |\ \/ / | |/ _ \ | |
* \ / | |_| | \ / | | __/ | |
* \/ \__,_| \/ |_|\____||_|
*
* Author: ~Noah-kun~
* Created: 2025-08-17 15:22
**/
#include <bits/stdc++.h>
using namespace std;
#define int long long
#define ____VuViet__ signed main
const int N = 1e5 + 5;
typedef pair<int, int> pii;
int cnt = 0, id = 0, n, m, k;
int num[N], low[N], comp[N], sum[N];
int res[N], inStk[N], vis[N];
set<pii> g1[N], g2[N];
stack<int> stk;
void Tarjan(int u, int p)
{
num[u] = low[u] = ++id;
inStk[u] = 1;
stk.push(u);
for (auto [v, id] : g1[u])
{
if (id == -p) continue;
if (!num[v])
{
Tarjan(v, id);
low[u] = min(low[u], low[v]);
} else if (inStk[v]) {
low[u] = min(low[u], num[v]);
}
}
if (low[u] >= num[u])
{
++cnt;
int v;
do
{
v = stk.top();
stk.pop();
inStk[v] = 0;
comp[v] = cnt;
} while (v != u);
}
}
void ReadData()
{
cin >> n >> m;
for (int i = 1; i <= m; i++)
{
int u, v;
cin >> u >> v;
g1[u].insert({v, i});
g1[v].insert({u, -i});
}
}
void DFS(int u, int edgeId, int way)
{
vis[u] = 1;
for (auto [v, id] : g2[u])
{
if (vis[v]) continue;
int nextWay = (id > 0) ? 1 : -1;
DFS(v, abs(id), nextWay);
sum[u] += sum[v];
}
if (sum[u] != 0 && edgeId != 0) {
res[edgeId] = (sum[u] * way > 0) ? 1 : 2;
}
}
char GetChar(int x)
{
if (x == 0) return 'B';
if (x == 1) return 'L';
return 'R';
}
void Solve()
{
for (int i = 1; i <= n; i++)
if (!num[i])
Tarjan(i, i);
for (int u = 1; u <= n; u++)
for (auto [v, id] : g1[u])
if (comp[u] != comp[v])
g2[comp[u]].insert({comp[v], id});
cin >> k;
while (k--)
{
int u, v;
cin >> u >> v;
++sum[comp[u]], --sum[comp[v]];
}
for (int i = 1; i <= cnt; i++)
if (!vis[i])
DFS(i, 0, 0);
for (int i = 1; i <= m; i++)
cout << GetChar(res[i]);
}
____VuViet__()
{
ReadData();
Solve();
return 0;
}
