/**
 * @author n685
 * @brief
 * @date 2024-08-21 17:05:01
 *
 *
 */
#include "bits/stdc++.h"

#ifdef LOCAL
#include "dd/debug.h"
#else
#define dbg(...) 42
#define dbg_proj(...) 420
#define dbg_rproj(...) 420420

void nline() {}

void bar() {}

void start_clock() {}

void end_clock() {}
#endif

void tarjan(
  int node,
  std::vector<int> &clr,
  std::vector<int> &dfn,
  int n,
  const std::vector<std::vector<int>> &adj
) {
  static int cnt = 0, num = 0;
  static std::vector<int> low(n, -1);
  static std::vector<bool> vis(n);
  static std::stack<int, std::vector<int>> st;
  dfn[node] = cnt++;
  low[node] = dfn[node];
  st.push(node);
  vis[node] = true;
  for (int i : adj[node]) {
    if (dfn[i] == -1) {
      tarjan(i, clr, dfn, n, adj);
    }
    if (vis[i]) {
      low[node] = std::min(low[node], low[i]);
    }
  }
  if (dfn[node] == low[node]) {
    while (!st.empty()) {
      int v = st.top();
      st.pop();
      clr[v] = num;
      vis[v] = false;
      if (node == v) {
        break;
      }
    }
    ++num;
  }
}

std::vector<int> scc(int n, const std::vector<std::vector<int>> &adj) {
  std::vector<int> clr(n, -1), dfn(n, -1);
  for (int i = 0; i < n; ++i) {
    if (dfn[i] == -1) {
      tarjan(i, clr, dfn, n, adj);
    }
  }
  return clr;
}

std::optional<std::vector<bool>> type1(
  int n,
  int thres,
  const std::vector<int> &sz,
  const std::vector<std::vector<int>> &adj,
  const std::vector<std::vector<int>> &radj
) {
  std::vector<int> in(n);
  std::queue<int> q;
  for (int i = 0; i < n; ++i) {
    in[i] = static_cast<int>(adj[i].size());
    if (in[i] == 0) {
      q.push(i);
    }
  }
  std::vector<bool> ans(n);
  int sum = 0;
  while (!q.empty()) {
    int node = q.front();
    q.pop();
    if (sz[node] >= thres) {
      continue;
    }
    sum += sz[node];
    ans[node] = true;
    if (sum >= thres) {
      return ans;
    }
    for (int i : radj[node]) {
      if (--in[i] == 0) {
        q.push(i);
      }
    }
  }
  return std::nullopt;
}

int dfs_type2(
  int node,
  std::vector<bool> &ans,
  const std::vector<int> &sz,
  const std::vector<std::vector<int>> &adj
) {
  int res = sz[node];
  ans[node] = true;
  for (int i : adj[node]) {
    res += dfs_type2(i, ans, sz, adj);
  }
  return res;
}

std::optional<std::vector<bool>> type2(
  int n,
  int thres,
  const std::vector<int> &sz,
  const std::vector<std::vector<int>> &adj
) {
  for (int i = 0; i < 3 * n; ++i) {
    if (sz[i] >= thres) {
      std::vector<bool> ans(n);
      if (dfs_type2(i, ans, sz, adj) <= 2 * thres) {
        return ans;
      }
    }
  }
  return std::nullopt;
}

void build(
  int node,
  int l,
  int r,
  int &sz,
  std::vector<int> &iin,
  std::vector<int> &iout,
  std::vector<std::vector<int>> &adj
) {
  if (l == r) {
    iin[node] = l;
    iout[node] = l;
    return;
  }
  iin[node] = sz++;
  iout[node] = sz++;
  adj.emplace_back();
  adj.emplace_back();
  int mid = (l + r) / 2;
  build(2 * node, l, mid, sz, iin, iout, adj);
  build(2 * node + 1, mid + 1, r, sz, iin, iout, adj);
  adj[iin[node]].push_back(iin[2 * node]);
  adj[iin[node]].push_back(iin[2 * node + 1]);
  adj[iout[2 * node]].push_back(iout[node]);
  adj[iout[2 * node + 1]].push_back(iout[node]);
}

enum class Dir : int8_t { IN, OUT };

void unite(
  int a,
  int b,
  int v,
  Dir dir,
  int node,
  int l,
  int r,
  std::vector<std::vector<int>> &adj,
  const std::vector<int> &iin,
  const std::vector<int> &iout
) {
  if (a <= l && r <= b) {
    if (dir == Dir::OUT) {
      adj[iout[node]].push_back(v);
    } else {
      adj[v].push_back(iin[node]);
    }
    return;
  }
  int mid = (l + r) / 2;
  if (a <= mid) {
    unite(a, b, v, dir, 2 * node, l, mid, adj, iin, iout);
  }
  if (b > mid) {
    unite(a, b, v, dir, 2 * node + 1, mid + 1, r, adj, iin, iout);
  }
}

void solve() {
  int n, q;
  std::cin >> n >> q;

  int bound = static_cast<int>(std::bit_ceil<uint32_t>(3 * n));

  std::vector<int> iin(2 * bound), iout(2 * bound);
  int cnt = bound;
  std::vector<std::vector<int>> adj(bound);
  build(1, 0, bound - 1, cnt, iin, iout, adj);
  for (int i = 0; i < q; ++i) {
    int a, b, c, d;
    std::cin >> a >> b >> c >> d;
    --a;
    --b;
    --c;
    --d;
    adj.emplace_back();
    unite(a, b, cnt + i, Dir::OUT, 1, 0, bound - 1, adj, iin, iout);
    unite(c, d, cnt + i, Dir::IN, 1, 0, bound - 1, adj, iin, iout);
  }
  std::vector<int> clr = scc(cnt + q, adj);
  int m = *std::ranges::max_element(clr) + 1;
  std::vector<int> sz(m);
  std::vector<std::vector<int>> sadj(m);
  std::vector<std::vector<int>> gr(m);
  for (int i = 0; i < cnt + q; ++i) {
    if (i < 3 * n) {
      ++sz[clr[i]];
      gr[clr[i]].push_back(i);
    }
    for (int j : adj[i]) {
      if (clr[i] != clr[j]) {
        sadj[clr[i]].push_back(clr[j]);
      }
    }
  }
  for (std::vector<int> &v : sadj) {
    std::ranges::sort(v);
    v.erase(std::unique(v.begin(), v.end()), v.end());
  }
  std::vector<std::vector<int>> sradj(m);
  for (int i = 0; i < m; ++i) {
    for (int j : sadj[i]) {
      sradj[j].push_back(i);
    }
  }

  std::optional<std::vector<bool>> opt = type1(m, n, sz, sadj, sradj);
  std::vector<bool> ans;
  if (opt.has_value()) {
    ans = *opt;
  } else {
    opt = type2(m, n, sz, sadj);
    if (opt.has_value()) {
      ans = *opt;
    } else {
      std::cout << "NIE\n";
      return;
    }
  }
  std::cout << "TAK\n";
  std::string val(3 * n, 'R');
  for (int i = 0; i < m; ++i) {
    if (ans[i]) {
      for (int j : gr[i]) {
        val[j] = 'F';
      }
    }
  }
  std::cout << val << '\n';
}

int main() {
#ifndef LOCAL
  std::ios::sync_with_stdio(false);
  std::cin.tie(nullptr);
#endif

  int z;
  std::cin >> z;
  for (int i = 0; i < z; ++i) {
    dbg(i + 1);
    solve();
    bar();
  }
}