#include <bits/stdc++.h>
using namespace std;
#define pii pair<int,int>
#define X first
#define Y second
const int N=1e5+5;
int n,m,request,x,y,timesdfs,tplt;
int save_x[N],save_y[N],low[N],num[N],scc[N],dp[N];
char ans[N];
bool visited[N];
vector <pii> adj[N],g[N];
stack <int> trace;
void dfs(int u,int root)
{
num[u]=low[u]=++timesdfs;
trace.push(u);
for (pii v:adj[u])
if (!scc[v.X])
{
if (v.Y!=root)
{
if (num[v.X]) low[u]=min(low[u],num[v.X]);
else
{
dfs(v.X,v.Y);
low[u]=min(low[u],low[v.X]);
}
}
}
if (num[u]==low[u])
{
tplt++;
int k=-1;
while (u!=k)
{
k=trace.top();
trace.pop();
scc[k]=tplt;
}
}
}
void final_dfs(int u)
{
visited[u]=true;
for (pii v:g[u])
if (!visited[v.X])
{
final_dfs(v.X);
if (dp[v.X]<0)
{
if (v.Y>0) ans[v.Y]='L';
else ans[-v.Y]='R';
}
if (dp[v.X]>0)
{
if (v.Y>0) ans[v.Y]='R';
else ans[-v.Y]='L';
}
dp[u]+=dp[v.X];
}
}
int main()
{
ios_base::sync_with_stdio(NULL);
cin.tie(NULL); cout.tie(NULL);
cin >> n >> m;
for (int i=1;i<=m;i++)
{
cin >> x >> y;
adj[x].push_back(make_pair(y,i));
adj[y].push_back(make_pair(x,i));
save_x[i]=x;
save_y[i]=y;
}
timesdfs=0;
for (int i=1;i<=n;i++)
if (!num[i]) dfs(i,-1);
for (int i=1;i<=m;i++)
{
x=scc[save_x[i]];
y=scc[save_y[i]];
if (x!=y)
{
g[x].push_back(make_pair(y,i));
g[y].push_back(make_pair(x,-i));
}
ans[i]='B';
}
for (int i=1;i<=tplt;i++)
dp[i]=0;
cin >> request;
while (request--)
{
cin >> x >> y;
x=scc[x];
y=scc[y];
if (x!=y)
{
dp[x]--;
dp[y]++;
}
}
for (int i=1;i<=tplt;i++)
if (!visited[i]) final_dfs(i);
for (int i=1;i<=m;i++)
cout << ans[i];
}
