// UUID: d5692679-dfc1-4bd7-84ce-11dadde4d66f
#include <bits/stdc++.h>
using namespace std;
#define int long long
#define F first
#define S second
#define pii pair<int,int>
#define pb push_back
#define srt(x) x.begin(),x.end()
vector<vector<pii>> g;
vector<pii> e;
vector<int> tin, low, p;
vector<int> ans;
vector<int> cnt;
int tim = 0;
void dfs(int v)
{
tin[v] = low[v] = ++tim;
for(auto [u, id] : g[v])
{
if(u == p[v]) continue;
if(!tin[u])
{
p[u] = v;
dfs(u);
low[v] = min(low[v], low[u]);
cnt[v] += cnt[u];
if(low[u] > tin[v])
{
if(cnt[u] > 0) ans[id] = 1;
else if(cnt[u] < 0) ans[id] = 2;
else ans[id] = 3;
}
else ans[id] = 3;
}
else
{
low[v] = min(low[v], tin[u]);
ans[id] = 3;
}
}
}
signed main()
{
ios::sync_with_stdio(false);cin.tie(nullptr);
int n, m; cin >> n >> m;
g.resize(n); tin.resize(n); low.resize(n); p.resize(n,-1); ans.resize(m); e.resize(m); cnt.resize(n);
for(int i = 0; i < m; i++)
{
int a, b; cin >> a >> b; --a;--b;
g[a].pb({b, i});
g[b].pb({a, i});
e[i] = {a, b};
}
int q; cin >> q;
while(q--)
{
int a, b; cin >> a >> b; --a;--b;
cnt[a]++;
cnt[b]--;
}
dfs(0);
for(int i = 0; i < m; i++)
{
if(ans[i] == 3) cout << 'B';
else if(ans[i] == 2)
{
if(e[i].F == p[e[i].S]) cout << 'R';
else cout << 'L';
}
else
{
if(e[i].F == p[e[i].S]) cout << 'L';
else cout << 'R';
}
}
}
