#include <bits/stdc++.h>
#define N 100050
#define logn 20
#define f first
#define s second
using namespace std;
typedef pair<int, int> pii;
int q, n, m, dfsnum[N], dfslow[N], cnt, pai[N];
int dp[N], ans[N];
int solved[N];
vector<int> pontes;
map<pii, int> ccnt;
vector<pii> G[N], A, grafo[N];
void dfs(int x)
{
dfsnum[x] = dfslow[x] = ++cnt;
for(int i = 0; i< G[x].size(); i++)
{
int v = G[x][i].f, id = G[x][i].s;
if(!dfsnum[v])
{
pai[v] = x;
dfs(v);
if(dfslow[v] > dfsnum[x] && ccnt[{ min(x, v), max(x, v) }] == 1 ) pontes.push_back(id);
dfslow[x] = min(dfslow[v], dfslow[x]);
}
else if(v != pai[x]) dfslow[x] = min(dfsnum[v], dfslow[x]);
}
}
int ok[N], esq[N], dir[N];
vector<pii> tree[N];
void get_tree(int x)
{
ok[x] = 1;
for(auto v: G[x])
{
if(ok[v.f]) continue;
tree[x].push_back(v);
tree[v.f].push_back({x, v.s});
get_tree(v.f);
}
}
int solve(int x, int p)
{
for(auto v: tree[x])
{
if(v.f == p) continue;
int child = solve(v.f, x);
bool brg = binary_search(pontes.begin(), pontes.end(), v.s);
if(child > 0 && brg)
{
if(esq[v.s] == x) ans[v.s] = -1;
else ans[v.s] = 1;
}
else if(child < 0 && brg)
{
if(esq[v.s] == x) ans[v.s] = 1;
else ans[v.s] = -1;
}
dp[x] += child;
}
solved[x] = 1;
return dp[x];
}
int main()
{
ios::sync_with_stdio(false); cin.tie(0);
cin>>n>>m;
for(int i = 1, a, b ;i <= m; i++)
{
cin>>a>>b;
G[a].push_back({b, i - 1});
G[b].push_back({a, i - 1});
A.push_back({a, b});
esq[i - 1] = a, dir[i - 1] = b;
ccnt[ {min(a, b), max(a, b)}] ++;
}
for(int i = 1; i <= n; i++) if(!dfsnum[i]) dfs(i);
for(auto id: pontes) grafo[ A[id].f ].push_back( {A[id].s, id} ), grafo[ A[id].s ].push_back( {A[id].f, id} );
cin>>q;
for(int i = 1, a, b; i <= q; i++)
{
cin>>a>>b;
dp[a] ++, dp[b] --;
}
sort(pontes.begin(), pontes.end());
for(int i = 1; i <= n; i++) if(ok[i] == 0) get_tree(i);
for(int i = 1; i <= n; i++) if(!solved[i]) solve(i, i);
for(int i = 0; i < m; i++)
{
if(ans[i] == 0) cout<<"B";
else if(ans[i] > 0) cout<<"R";
else cout<<"L";
}
cout<<"\n";
}
