import std.conv, std.functional, std.range, std.stdio, std.string;
import std.algorithm, std.array, std.bigint, std.bitmanip, std.complex, std.container, std.math, std.mathspecial, std.numeric, std.regex, std.typecons;
import core.bitop;

class EOFException : Throwable { this() { super("EOF"); } }
string[] tokens;
string readToken() { for (; tokens.empty; ) { if (stdin.eof) { throw new EOFException; } tokens = readln.split; } auto token = tokens.front; tokens.popFront; return token; }
int readInt() { return readToken.to!int; }
long readLong() { return readToken.to!long; }
real readReal() { return readToken.to!real; }

bool chmin(T)(ref T t, in T f) { if (t > f) { t = f; return true; } else { return false; } }
bool chmax(T)(ref T t, in T f) { if (t < f) { t = f; return true; } else { return false; } }

int binarySearch(alias pred, T)(in T[] as) { int lo = -1, hi = cast(int)(as.length); for (; lo + 1 < hi; ) { const mid = (lo + hi) >> 1; (unaryFun!pred(as[mid]) ? hi : lo) = mid; } return hi; }
int lowerBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a >= val)); }
int upperBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a > val)); }


int root(int[] uf, int u) {
  return (uf[u] < 0) ? u : (uf[u] = uf.root(uf[u]));
}
bool connect(int[] uf, int u, int v) {
  u = uf.root(u);
  v = uf.root(v);
  if (u == v) return false;
  if (uf[u] > uf[v]) swap(u, v);
  uf[u] += uf[v];
  uf[v] = u;
  return true;
}


int N;
int[] C, D;

bool solve() {
  const V = N + 3;
  auto uf = new int[V];
  uf[] = -1;
  foreach (i; 0 .. N) {
    uf.connect(N + C[i], D[i]);
  }
  const r = uf.root(D[0]);
  foreach (i; 0 .. N) {
    if (r != uf.root(D[i])) {
      return false;
    }
  }
  
  auto hasColor = new bool[3];
  auto has = new bool[][](3, N);
  foreach (i; 0 .. N) {
    hasColor[C[i]] = true;
    has[C[i]][D[i]] = true;
  }
  if (hasColor.count(true) < 3) {
    return true;
  }
  foreach (c; 0 .. 3) {
    int[] ds1, ds2;
    const c1 = (c + 1) % 3;
    const c2 = (c + 2) % 3;
    foreach (d; 0 .. N) {
      if (has[c][d] && has[c1][d]) ds1 ~= d;
      if (has[c][d] && has[c2][d]) ds2 ~= d;
    }
    assert(!ds1.empty);
    assert(!ds2.empty);
    if (ds1.length == 1 && ds2.length == 1 && ds1[0] == ds2[0]) {
      if (has[c].count(true) == 1) {
        return true;
      }
    } else {
      return true;
    }
  }
  return false;
}

void main() {
  try {
    for (; ; ) {
      const numCases = readInt;
      foreach (caseId; 0 .. numCases) {
        N = readInt;
        C = new int[N];
        D = new int[N];
        foreach (i; 0 .. N) {
          C[i] = cast(int)("BGR".indexOf(readToken[0]));
          D[i] = readInt - 1;
        }
        
        const ans = solve;
        writeln(ans ? "YES" : "NO");
      }
    }
  } catch (EOFException e) {
  }
}