# define NDEBUG

# include <cstdlib>
# include <cassert>
# include <cstring>
# include <vector>
# include <algorithm>
# include <iostream>
# include <istream>
# include <ostream>

namespace khin {
  using namespace std;
  namespace ucup {
    inline namespace source {}
    namespace ucup1 {
      namespace stage03 {
        namespace f { void main(); }
      }
    }
  }
}

int main() { khin::ucup::ucup1::stage03::f::main(); }

namespace khin::ucup::ucup1::stage03::f {
  namespace test_case {
    constexpr uint n_max(33'333), q_max(100'000);
    inline uint next_index();
    inline void set(uint, uint);
    inline void add(uint, uint);
    class segment_tree {
      constexpr static uint lg_max = __lg(3 * n_max + 1) + 1;
      uint lg, s[1 << (lg_max + 1)], t[1 << (lg_max + 1)];
      public:
      segment_tree() {}
      void assign(uint const n) {
        lg = __lg(3 * n + 1) + 1;
        for (uint i(0); i != 1u << lg; ++i) {
          s[1 << lg | i] = next_index();
          t[1 << lg | i] = next_index();
          assert(s[1 << lg | i] == (i << 1 | 0));
          assert(t[1 << lg | i] == (i << 1 | 1));
          if (1 <= i && i <= 3 * n) set(s[1 << lg | i], 1);
          add(t[1 << lg | i], s[1 << lg | i]);
        }
        for (uint i((1u << lg) - 1); i; --i) {
          s[i] = next_index(), t[i] = next_index();
          add(s[i << 1 | 0], s[i]), add(s[i << 1 | 1], s[i]);
          add(t[i], t[i << 1 | 0]), add(t[i], t[i << 1 | 1]);
        }
        assert(t[1] == 2 * (1u << (lg + 1)) - 3);
      }
      void adds(uint l, uint r, uint const x) const {
        --l |= 1 << lg, ++r |= 1 << lg;
        while ((l ^ r) >> 1) {
          if ((l & 1) == 0) add(s[l ^ 1], x);
          if ((r & 1) == 1) add(s[r ^ 1], x);
          l >>= 1, r >>= 1;
        }
      }
      void addt(uint l, uint r, uint const x) const {
        --l |= 1 << lg, ++r |= 1 << lg;
        while ((l ^ r) >> 1) {
          if ((l & 1) == 0) add(x, t[l ^ 1]);
          if ((r & 1) == 1) add(x, t[r ^ 1]);
          l >>= 1, r >>= 1;
        }
      }
      void addr(uint const a, uint const b, uint const c, uint const d) const {
        uint const x(next_index());
        assert(x >= 2 * (1u << (lg + 1)) - 2);
        assert(x - 2 * (1u << (lg + 1)) + 2 < q_max);
        adds(a, b, x), addt(c, d, x);
      }
    };
    class graph {
      constexpr static uint v_max
        = 2 * (1 << (__lg(3 * n_max + 1) + 2)) + q_max;
      struct vertex0 { vector<uint> t; uint index, low, scc; uint val; };
      struct vertex1 { vector<uint> s, t; uint sum; bool vis; };
      vertex0 v0[v_max]; uint p, index, num; vertex1 v1[v_max + 1];
      void tarjan(uint const x) {
        static uint stk[v_max], *top(stk);
        v0[x].low = v0[x].index = ++index, *top++ = x;
        for (uint const t : v0[x].t)
          if (!v0[t].index) tarjan(t), v0[x].low = min(v0[x].low, v0[t].low);
          else if (!v0[t].scc) v0[x].low = min(v0[x].low, v0[t].index);
        if (v0[x].low == v0[x].index)
        { ++num; while (v0[*--top].scc = num, *top != x); }
      }
      uint sums(uint const x) {
        if (v1[x].vis) return 0; else v1[x].vis = true;
        uint res(v1[x].sum);
        for (uint const s : v1[x].s) res += sums(s);
        return res;
      }
      uint sumt(uint const x) {
        if (v1[x].vis) return 0; else v1[x].vis = true;
        uint res(v1[x].sum);
        for (uint const t : v1[x].t) res += sumt(t);
        return res;
      }
      public:
      void clear() {
        fill(v0, v0 + p, vertex0());
        fill(v1 + 1, v1 + num + 1, vertex1());
        num = index = p = 0;
      }
      uint next_index() { return p++; }
      void set(uint const x, uint const v) { this->v0[x].val = v; }
      void add(uint const s, uint const t) { v0[s].t.push_back(t); }
      string solve(uint const n) {
        for (uint i(0); i < p; ++i) if (!v0[i].index) tarjan(i);
        for (uint i(0); i < p; ++i) v1[v0[i].scc].sum += v0[i].val;
        uint tot(0);
        for (uint i(1); i <= num; ++i)
          if ((tot += v1[i].sum) >= n && tot <= 2 * n) {
            string s(3 * n, ' ');
            for (uint j(1); j <= 3 * n; ++j)
              s[j - 1] = v0[j << 1 | 0].scc <= i ? 'F' : 'R';
            return s;
          }
        for (uint i(1); i <= num; ++i) if (v1[i].sum > n) {
          if (sums(i) <= 2 * n) {
            string s(3 * n, ' ');
            for (uint j(1); j <= 3 * n; ++j)
              s[j - 1] = v1[v0[j << 1 | 0].scc].vis ? 'F' : 'R';
            for (uint j(1); j <= num; ++j) v1[j].vis = false;
            return s;
          }
          for (uint j(1); j <= num; ++j) v1[j].vis = false;
          if (sumt(i) <= 2 * n) {
            string s(3 * n, ' ');
            for (uint j(1); j <= 3 * n; ++j)
              s[j - 1] = v1[v0[j << 1 | 0].scc].vis ? 'F' : 'R';
            for (uint j(1); j <= num; ++j) v1[j].vis = false;
            return s;
          }
          for (uint j(1); j <= num; ++j) v1[j].vis = false;
        }
        return string();
      }
    };
    uint n, q; segment_tree seg; graph g;
    inline uint next_index() { return g.next_index(); }
    inline void set(uint const x, uint const v) { g.set(x, v); }
    inline void add(uint const s, uint const t) { g.add(s, t); }
    void main() {
      cin >> n >> q, seg.assign(n);
      for (uint i(0); i < q; ++i) {
        uint a, b, c, d;
        cin >> a >> b >> c >> d;
        seg.addr(a, b, c, d);
      }
      string const ans(g.solve(n));
      if (ans.empty()) cout << "NIE" << endl;
      else cout << "TAK" << endl << ans << endl;
      g.clear();
    }
  }
  void main() {
    uint z; cin >> z;
    for (uint i(1); i <= z; ++i) test_case::main();
  }
}