#include <iostream>
#include <vector>
#include <algorithm>
#include <queue>
using namespace std;
using vi = vector<int>;
using vvi = vector<vi>;
using pii = pair<int, int>;
const int mx = 100'000;
int n, m;
vi edge[1+mx];
vi nw_edge[1+mx];
vi nw_rev[1+mx];
vi visit(1+mx, 0);
vi ee;
void dfs(int u, int p)
{
visit[u] = 1;
for(int v: edge[u])
{
if(v == p) continue;
if(visit[v])
{
// cerr << v << " ->* " << u << '\n';
nw_edge[v].push_back(u);
nw_rev[u].push_back(v);
}
else
{
// cerr << u << " -> " << v << '\n';
nw_edge[u].push_back(v);
nw_rev[v].push_back(u);
dfs(v, u);
}
}
ee.push_back(u);
}
vi bcc(1+mx, 0);
int ct = 0;
vi bcc_list[1+mx];
void dfs2(int u)
{
bcc[u] = ct;
bcc_list[ct].push_back(u);
for(int v: nw_rev[u])
{
if(bcc[v]) continue;
dfs2(v);
}
}
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cin >> n >> m;
vi a(1+m), b(1+m);
for(int e = 1; e <= m; e++)
{
cin >> a[e] >> b[e];
edge[a[e]].push_back(b[e]);
edge[b[e]].push_back(a[e]);
}
for(int u = 1; u <= n; u++)
{
if(visit[u]) continue;
dfs(u, 0);
}
// for(int u = 1; u <= n; u++)
// {
// cerr << u << " : ";
// for(int v: nw_edge[u]) cerr << v << ' ';
// cerr << '\n';
// }
reverse(ee.begin(), ee.end());
for(int u: ee)
{
if(bcc[u]) continue;
++ct;
dfs2(u);
}
// for(int i = 1; i <= ct; i++)
// {
// for(int u: bcc_list[i]) cerr << u << ' ';
// cerr << '\n';
// }
vector<pii> bcc_edge[1+ct];
vi deg(1+ct, 0);
vector<char> ans(1+m, 'B');
for(int e = 1; e <= m; e++)
{
if(bcc[a[e]] == bcc[b[e]])
{
continue;
}
bcc_edge[ bcc[a[e]] ].push_back({bcc[b[e]], +e});
bcc_edge[ bcc[b[e]] ].push_back({bcc[a[e]], -e});
deg[bcc[a[e]]]++;
deg[bcc[b[e]]]++;
}
vi score(1+ct, 0);
int p;
cin >> p;
for(int z = 1; z <= p; z++)
{
int x, y;
cin >> x >> y;
score[bcc[x]]++;
score[bcc[y]]--;
}
fill(visit.begin(), visit.end(), 0);
queue<int> tbv;
for(int u = 1; u <= ct; u++)
{
if(deg[u] == 1)
{
tbv.push(u);
}
}
while(!tbv.empty())
{
int u = tbv.front();
tbv.pop();
deg[u] = -5;
// cerr << "u = " << u << " : ";
// for(int w: bcc_list[u]) cerr << w << ' ';
// cerr << '\n';
for(pii e: bcc_edge[u])
{
int v = e.first;
int id = e.second;
if(deg[v] < 0) continue;
deg[v]--;
// cerr << "par " << u << " = " << v << '\n';
// cerr << score[u] << '\n';
if(score[u] > 0)
{
// cerr << "#\n";
if(id > 0)
ans[id] = 'R';
else
ans[-id] = 'L';
}
else if(score[u] < 0)
{
// cerr << "? " << id << '\n';
if(id > 0)
ans[id] = 'L';
else
ans[-id] = 'R';
}
score[v] += score[u];
score[u] = 0;
if(deg[v] == 1) tbv.push(v);
}
}
for(int e = 1; e <= m; e++) cout << ans[e];
cout << '\n';
}
