#include<bits/stdc++.h>
using namespace std;
// define
#define execute cerr << " Time: " << fixed << setprecision(6) << (1.0 * clock() / CLOCKS_PER_SEC) << "s\n";
#define ll long long
#define ld double
#define ii pair<int,int>
#define se second
#define fi first
#define iii pair<int,ii>
#define all(v) v.begin(),v.end()
#define bit(x,i) (((x)>>(i))&1LL)
#define flip(x,i) ((x)^(1LL<<(i)))
#define ms(d,x) memset(d,x,sizeof(d))
#define sitingfake 1
#define orz 1
#define exist __exist
#define ends __ends
#define visit visited
#define left __left
#define right __right
//constant
const ll mod = 1e9 + 7;
const long long linf = 4557430888798830399;
const int inf = 1061109567;
const int maxarr = 1e6 + 5;
int dx[] = {0 , -1 , 0 , 1};
int dy[] = {-1 , 0 , 1 , 0};
template<typename T> bool maximize(T &a, const T &b)
{
if(a < b) {a = b; return 1;}
return 0;
}
template<typename T> bool minimize(T &a, const T &b)
{
if(a > b) {a = b; return 1;}
return 0;
}
inline void Plus(ll & a ,ll b)
{
b %= mod;
a += b;
if(a >= mod) a -= mod;
if(a < 0) a += mod;
return;
}
inline void Mul(ll & a, ll b)
{
a %= mod; b %= mod;
a *= b;
a %= mod;
return;
}
//code
const int maxn = 1e5 + 7;
ii edges[maxn];
char ans[maxn];
vector <iii> g[maxn];
vector <ii> a[maxn];
vector <int> roots;
int low[maxn] , id[maxn] , scc[maxn] , components , timer;
int in[maxn] , out[maxn];
stack <int> st;
int depth[maxn] , par[maxn][20];
int dp[maxn];
int n , m , q;
void dfs(int u , int p)
{
low[u] = id[u] = ++timer;
st.push(u);
for(ii i : a[u])
{
int v = i.fi;
int np = i.se;
if(np == p) continue;
if(!id[v])
{
dfs(v , np);
low[u] = min(low[u] , low[v]);
}
else low[u] = min(low[u] , id[v]);
}
if(low[u] == id[u])
{
++components;
int v;
do
{
v = st.top();
st.pop();
scc[v] = components;
}while(v != u);
}
}
void DFS(int u , int p)
{
in[u] = ++timer;
for(iii it : g[u])
{
int v = it.se.fi;
if(v != p)
{
DFS(v , u);
}
}
out[u] = timer;
}
bool inside(int u , int v)
{
return in[u] <= in[v] && out[v] <= out[u];
}
void Push(int u , int p)
{
for(iii i : g[u])
{
int t = i.fi;
int id = i.se.se;
int v = i.se.fi;
if(v != p)
{
Push(v , u);
dp[u] += dp[v];
if(dp[v] >= 1)
{
if(!t) ans[id] = 'L';
else ans[id] = 'R';
}
else if(dp[v] <= -1)
{
if(!t) ans[id] = 'R';
else ans[id] = 'L';
}
else ans[id] = 'B';
}
}
}
void solve(void)
{
cin >> n >> m;
for(int i = 1; i <= m; i++)
{
int u , v;
cin >> u >> v;
edges[i] = ii(u , v);
a[u].push_back(ii(v , i));
a[v].push_back(ii(u , i));
}
for(int i = 1; i <= n; i++)
{
if(!id[i])
{
dfs(i , -1);
}
}
for(int i = 1; i <= m; i++)
{
int u = edges[i].fi;
int v = edges[i].se;
if(scc[u] == scc[v])
{
ans[i] = 'B';
}
else
{
u = scc[u];
v = scc[v];
g[u].push_back(iii(0 , ii(v , i)));
g[v].push_back(iii(1 , ii(u , i)));
}
}
timer = 0;
for(int i = 1; i <= components; i++)
{
if(!in[i])
{
roots.push_back(i);
DFS(i , -1);
}
}
cin >> q;
while(q--)
{
int u , v;
cin >> u >> v;
if(scc[u] != scc[v])
{
u = scc[u] , v = scc[v];
dp[u]++;
dp[v]--;
}
}
for(int i : roots)
{
Push(i , -1);
}
for(int i = 1; i <= m; i++) cout << ans[i];
}
/**
**/
signed main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
#define task ""
if(fopen(task".inp","r"))
{
freopen(task".inp","r",stdin);
freopen(task".out","w",stdout);
}
int tc; tc = 1;
while(tc--) solve();
//execute;
}
