#include <iostream>
#include <vector>
#include <cstring>
#include <queue>
using namespace std;
const int lim = 1e5 + 5;
int n,m, low[lim], disc[lim], visited[lim], timer = 0, p2[50];
int bridge[lim], tree_code[lim], parent[50][lim], depth[lim], save[lim];
vector <pair <int,int>> path[lim], tree[lim], rtree[lim];
pair <int,int> pathing[lim];
char ans[lim];
void dfs(int pos, int id)
{
low[pos] = disc[pos] = timer;
timer++;
for(auto [i,code] : path[pos])
{
if(code == id)
continue;
if(visited[i])
{
low[pos] = min(low[pos], disc[i]);
}
else
{
visited[i] = true;
dfs(i, code);
low[pos] = min(low[i], low[pos]);
if(low[i] > disc[pos])
{
bridge[code] = true;
}
}
}
return;
}
void dfs2(int pos, int par)
{
visited[pos] = true;
for(auto [i, code] : tree[pos])
{
if(i != par)
{
rtree[pos].push_back({i, code});
parent[0][i] = pos;
dfs2(i,pos);
}
}
return;
}
void compute_depth(int pos, int curr_depth)
{
depth[pos] = curr_depth;
for(auto [i,code] : rtree[pos])
{
compute_depth(i,curr_depth + 1);
}
return;
}
void precomputation(int pos)
{
for(int i = 1 ; i <= 30 ; i++)
{
parent[i][pos] = parent[i - 1][parent[i - 1][pos]];
}
for(auto [i,code] : rtree[pos])
precomputation(i);
return;
}
pair <int, int> dist_lca(int a, int b)
{
int ans1 = 0, ans2 = 0;
for(int x = 30 ; x >= 0 ; x--)
{
if(depth[a] - depth[b] >= p2[x])
{
ans1 += p2[x];
a = parent[x][a];
}
if(depth[b] - depth[a] >= p2[x])
{
ans2 += p2[x];
b = parent[x][b];
}
}
//depth sudah sama
if(a == b)
return {ans1, ans2};
for(int x = 30 ; x >= 0 ; x--)
{
if(parent[x][a] != parent[x][b])
{
a = parent[x][a], b = parent[x][b];
ans1 += p2[x], ans2 += p2[x];
}
}
if(parent[0][a] == parent[0][b])
return {ans1 + 1, ans2 + 1};
return {-1,-1};
}
int dfsfin(int pos)
{
int coded = save[pos];
for(auto [i, id] : rtree[pos])
{
int val = dfsfin(i);
auto [u,v] = pathing[id];
if(val < 0)
{
//turun
val++;
coded = min(coded,val);
if(u == pos && v == i)
ans[id] = 'R';
else
ans[id] = 'L';
}
else if(val > 0)
{
//naik
val--;
coded = max(coded,val);
if(u == pos && v == i)
ans[id] = 'L';
else
ans[id] = 'R';
}
}
//if(coded > 0) coded--;
//else coded++;
return coded;
}
int main()
{
memset(save,0,sizeof(save));
p2[0] = 1;
for(int i = 1 ; i <= 30 ; i++)
p2[i] = p2[i - 1]*2;
scanf("%d %d", &n, &m);
memset(visited,0,sizeof(visited));
for(int i = 1 ; i <= m ; i++)
{
int a,b;
scanf("%d %d", &a, &b);
path[a].push_back({b,i});
path[b].push_back({a,i});
pathing[i] = {a,b};
}
for(int i = 1 ; i <= n ; i++)
{
if(!visited[i])
dfs(i,-1);
}
int tree_id = 1;
memset(tree_code,-1,sizeof(tree_code));
for(int i = 1 ; i <= n ; i++)
{
if(tree_code[i] == -1)
{
queue <int> que;
que.push(i);
while(!que.empty())
{
int pos = que.front();
que.pop();
if(tree_code[pos] == -1)
{
tree_code[pos] = tree_id;
for(auto [i, code] : path[pos])
{
if(bridge[code])
{
tree[tree_id].push_back({i, code});
}
else
que.push(i);
}
}
}
tree_id++;
}
}
/*
printf("DEBUG Bridge:\n");
for(int i = 1 ; i <= m ; i++)
printf("%d -> %d\n", i, bridge[i]);
printf("DEBUG Tree Code:\n");
for(int i = 1 ; i <= n ; i++)
printf("%d ", tree_code[i]);
printf("\n");
*/
for(int i = 1 ; i <= n ; i++)
{
for(int j = 0 ; j < tree[i].size() ; j++)
tree[i][j].first = tree_code[tree[i][j].first];
}
memset(visited,0,sizeof(visited));
for(int i = 1 ; i <= n ; i++)
{
if(!visited[i])
{
dfs2(i,-1);
compute_depth(i,0);
precomputation(i);
}
}
int q;
scanf("%d", &q);
for(int i = 1 ; i <= q ; i++)
{
int a,b;
scanf("%d %d", &a, &b);
a = tree_code[a], b = tree_code[b];
pair <int,int> val = dist_lca(a, b);
//printf("mark %d %d -> %d %d\n", a,b, val.first, val.second);
save[a] = max(save[a], val.first);
save[b] = min(save[b], -1*val.second);
}
memset(visited,0,sizeof(visited));
for(int i = 1 ; i <= n ; i++)
{
if(!visited[i])
dfsfin(i);
}
for(int i = 1 ; i <= m ; i++)
{
if(ans[i] != 'L' && ans[i] != 'R')
ans[i] = 'B';
printf("%c", ans[i]);
}
printf("\n");
}
