#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define ld long double
#define ar array
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
template <typename T> using oset = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
#define vt vector
#define pb push_back
#define all(c) (c).begin(), (c).end()
#define sz(x) (int)(x).size()
#define pll pair<ll, ll>
#define pii pair<int, int>
#define f first
#define s second
#define F_OR(i, a, b, s) for (int i=(a); (s)>0?i<(b):i>(b); i+=(s))
#define F_OR1(e) F_OR(i, 0, e, 1)
#define F_OR2(i, e) F_OR(i, 0, e, 1)
#define F_OR3(i, b, e) F_OR(i, b, e, 1)
#define F_OR4(i, b, e, s) F_OR(i, b, e, s)
#define GET5(a, b, c, d, e, ...) e
#define F_ORC(...) GET5(__VA_ARGS__, F_OR4, F_OR3, F_OR2, F_OR1)
#define FOR(...) F_ORC(__VA_ARGS__)(__VA_ARGS__)
#define EACH(x, a) for (auto& x: a)
template<class T> bool umin(T& a, const T& b) {
return b<a?a=b, 1:0;
}
template<class T> bool umax(T& a, const T& b) {
return a<b?a=b, 1:0;
}
ll FIRSTTRUE(function<bool(ll)> f, ll lb, ll rb) {
while(lb<rb) {
ll mb=(lb+rb)/2;
f(mb)?rb=mb:lb=mb+1;
}
return lb;
}
ll LASTTRUE(function<bool(ll)> f, ll lb, ll rb) {
while(lb<rb) {
ll mb=(lb+rb+1)/2;
f(mb)?lb=mb:rb=mb-1;
}
return lb;
}
template<class A> void read(vt<A>& v);
template<class A, size_t S> void read(ar<A, S>& a);
template<class A, class B> void read(pair<A, B>& x);
template<class T> void read(T& x) {
cin >> x;
}
void read(double& d) {
string t;
read(t);
d=stod(t);
}
void read(long double& d) {
string t;
read(t);
d=stold(t);
}
template<class H, class... T> void read(H& h, T&... t) {
read(h);
read(t...);
}
template<class A> void read(vt<A>& x) {
EACH(a, x)
read(a);
}
template<class A, size_t S> void read(array<A, S>& x) {
EACH(a, x)
read(a);
}
template<class A, class B> void read(pair<A, B>& x) {
cin >> x.first >> x.second;
}
string to_string(char c) {
return string(1, c);
}
string to_string(bool b) {
return b?"true":"false";
}
string to_string(const char* s) {
return string(s);
}
string to_string(string s) {
return s;
}
string to_string(vt<bool> v) {
string res;
FOR(sz(v))
res+=char('0'+v[i]);
return res;
}
template<size_t S> string to_string(bitset<S> b) {
string res;
FOR(S)
res+=char('0'+b[i]);
return res;
}
template<class T> string to_string(T v) {
bool f=1;
string res;
EACH(x, v) {
if(!f)
res+=' ';
f=0;
res+=to_string(x);
}
return res;
}
template<class A, class B> string to_string(pair<A, B>& x) {
return to_string(x.first) + ' ' + to_string(x.second);
}
template<class A> void write(A x) {
cout << to_string(x);
}
template<class H, class... T> void write(const H& h, const T&... t) {
write(h);
write(t...);
}
void print() {
write("\n");
}
template<class H, class... T> void print(const H& h, const T&... t) {
write(h);
if(sizeof...(t))
write(' ');
print(t...);
}
template<typename T, bool max>
struct RMQ {
int level(int x) { return 31-__builtin_clz(x); }
vt<T> v; vt<vt<int>> jmp;
int cmb(int a, int b) {
return v[a]==v[b]?min(a,b):(((v[a]<v[b])^max)?a:b); }
void init(const vt<T>& _v) {
v = _v; jmp = {vt<int>(sz(v))};
iota(all(jmp[0]),0);
for (int j = 1; 1<<j <= sz(v); ++j) {
jmp.pb(vt<int>(sz(v)-(1<<j)+1));
FOR(i,sz(jmp[j])) jmp[j][i] = cmb(jmp[j-1][i],
jmp[j-1][i+(1<<(j-1))]);
}
}
int index(int l, int r) {
assert(l <= r); int d = level(r-l+1);
return cmb(jmp[d][l],jmp[d][r-(1<<d)+1]); }
T query(int l, int r) { return v[index(l,r)]; }
};
#define MX 100000
int n, m, k;
vt<pii> adj[MX];
bool vis[MX], br[MX];
int d[MX], dp[MX], ti[MX], to[MX], t, e[MX], st[MX];
void dfs(int v, int p) {
ti[v]=t++;
vis[v]=1;
d[v]=d[p]+1;
bool sc=1;
for (auto &[u, ei] : adj[v]) {
if (sc && u==p) {
sc=0;
continue;
}
if (!vis[u]) {
e[u]=ei;
dfs(u, v);
dp[v]+=dp[u];
} else {
if (d[v]<d[u]) {
dp[v]--;
} else if (d[v]>d[u]) {
dp[v]++;
}
}
}
to[v]=t;
}
int main() {
ios::sync_with_stdio(0);
cin.tie(0);
read(n, m);
int x, y;
FOR(m) {
read(x, y); --x, --y;
st[i]=x;
adj[x].pb({y, i}), adj[y].pb({x, i});
}
FOR(n) {
if (!vis[i]) {
e[i]=-1;
d[i]=-1;
dfs(i, i);
}
}
RMQ<int, false> inmi, outmi;
RMQ<int, true> inma, outma;
vt<int> vinmi(n, INT_MAX), voutmi(n, INT_MAX), vinma(n, INT_MIN), voutma(n, INT_MIN);
read(k);
FOR(k) {
read(x, y);
y=ti[--y], x=ti[--x];
umin(vinmi[y], x), umax(vinma[y], x);
umin(voutmi[x], y), umax(voutma[x], y);
}
inmi.init(vinmi), inma.init(vinma), outmi.init(voutmi), outma.init(voutma);
string ans(m, 'B');
FOR(n) {
if (dp[i]==0 && e[i]!=-1) {
bool b=(i==st[e[i]]);
if (inmi.query(ti[i], to[i]-1)<ti[i] || inma.query(ti[i], to[i]-1)>=to[i]) {
ans[e[i]]=b ? 'L' : 'R';
}
if (outmi.query(ti[i], to[i]-1)<ti[i] || outma.query(ti[i], to[i]-1)>=to[i]) {
ans[e[i]]=b ? 'R' : 'L';
}
}
}
print(ans);
}
