#include<bits/stdc++.h>
constexpr int maxn = 2e5 + 10;
std::vector<int> son[maxn], to[maxn];
int k, pr[maxn];
void dfs(int u) {
   if (son[u].empty()) {
      pr[u] = u, k++;
   } else {
      for (int v : son[u]) {
         dfs(v);
         if (pr[u] && pr[v]) {
            to[pr[u]].push_back(pr[v]);
            to[pr[v]].push_back(pr[u]);
            pr[u] = 0;
         } else {
            pr[u] |= pr[v];
         }
      }
   }
}
inline void solve(int n) {
   for (int i = 1; i <= n; i++) son[i].clear();
   for (int i = 1, f; i < n; i++) {
      scanf("%d", &f), son[f].push_back(i);
   }
   dfs(n);
}
int col[maxn];
void dfsc(int u, int c) {
   if (col[u]) return ;
   col[u] = c;
   for (int v : to[u]) {
      dfsc(v, 3 - c);
   }
} 
inline void solve() {
   int n, m;
   scanf("%d%d", &n, &m);
   for (int i = 1; i <= n; i++) to[i].clear();
   k = 0;
   solve(n), solve(m);
   k >>= 1;
   memset(col + 1, 0, sizeof(int) * k);
   for (int i = 1; i <= k; i++) {
      dfsc(i, 1);
      putchar(" RB"[col[i]]);
   }
   puts("");
}
int main() {
   for (int T, _ = scanf("%d", &T); T--; ) {
      solve();
   }
   return 0;
}