#include<bits/stdc++.h>
#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/tree_policy.hpp>
#include<ext/pb_ds/tag_and_trait.hpp>
#define overload4(_1, _2, _3, _4, name, ...) name
#define rep1(i, n) for (ll i = 0; i < ll(n); ++i)
#define rep2(i, s, n) for (ll i = ll(s); i < ll(n); ++i)
#define rep3(i, s, n, d) for(ll i = ll(s); i < ll(n); i+=d)
#define rep(...) overload4(__VA_ARGS__,rep3,rep2,rep1)(__VA_ARGS__)
#define rrep1(i, n) for (ll i = ll(n)-1; i >= 0; i--)
#define rrep2(i, n, t) for (ll i = ll(n)-1; i >= (ll)t; i--)
#define rrep3(i, n, t, d) for (ll i = ll(n)-1; i >= (ll)t; i-=d)
#define rrep(...) overload4(__VA_ARGS__,rrep3,rrep2,rrep1)(__VA_ARGS__)
#define all(a) a.begin(),a.end()
#define rall(a) a.rbegin(),a.rend()
#define SUM(a) accumulate(all(a),0LL)
#define MIN(a) *min_element(all(a))
#define MAX(a) *max_element(all(a))
#define SORT(a) sort(all(a));
#define REV(a) reverse(all(a));
#define SZ(a) int(a.size())
#define popcount(x) __builtin_popcountll(x)
#define pf push_front
#define pb push_back
#define ef emplace_front
#define eb emplace_back
#define ppf pop_front
#define ppb pop_back
#ifdef __LOCAL
#define debug(...) { cout << #__VA_ARGS__; cout << ": "; print(__VA_ARGS__); cout << flush; }
#else
#define debug(...) void(0);
#endif
#define INT(...) int __VA_ARGS__;scan(__VA_ARGS__)
#define LL(...) ll __VA_ARGS__;scan(__VA_ARGS__)
#define STR(...) string __VA_ARGS__;scan(__VA_ARGS__)
#define CHR(...) char __VA_ARGS__;scan(__VA_ARGS__)
#define DBL(...) double __VA_ARGS__;scan(__VA_ARGS__)
#define LD(...) ld __VA_ARGS__;scan(__VA_ARGS__)
using namespace std;
using namespace __gnu_pbds;
using ll = long long;
using ld = long double;
using P = pair<int, int>;
using LP = pair<ll, ll>;
using vi = vector<int>;
using vvi = vector<vi>;
using vvvi = vector<vvi>;
using vl = vector<ll>;
using vvl = vector<vl>;
using vvvl = vector<vvl>;
using vd = vector<double>;
using vvd = vector<vd>;
using vs = vector<string>;
using vc = vector<char>;
using vvc = vector<vc>;
using vb = vector<bool>;
using vvb = vector<vb>;
using vp = vector<P>;
using vvp = vector<vp>;
using vlp = vector<LP>;
using vvlp = vector<vlp>;
template<class T>
using PQ = priority_queue<T>;
template<class T>
using PQrev = priority_queue<T, vector<T>, greater<T>>;

template<class S, class T>
istream &operator>>(istream &is, pair<S, T> &p) { return is >> p.first >> p.second; }

template<class S, class T>
ostream &operator<<(ostream &os, const pair<S, T> &p) { return os << '{' << p.first << ", " << p.second << '}'; }

template<class S, class T, class U>
istream &operator>>(istream &is, tuple<S, T, U> &t) { return is >> get<0>(t) >> get<1>(t) >> get<2>(t); }

template<class S, class T, class U>
ostream &operator<<(ostream &os, const tuple<S, T, U> &t) {
    return os << '{' << get<0>(t) << ", " << get<1>(t) << ", " << get<2>(t) << '}';
}

template<class T>
istream &operator>>(istream &is, vector<T> &v) {
    for (T &t: v) { is >> t; }
    return is;
}

template<class T>
ostream &operator<<(ostream &os, const vector<T> &v) {
    os << '[';
    rep(i, v.size()) os << v[i] << (i == int(v.size() - 1) ? "" : ", ");
    return os << ']';
}

template<class T>
ostream &operator<<(ostream &os, const deque<T> &v) {
    os << '[';
    rep(i, v.size()) os << v[i] << (i == int(v.size() - 1) ? "" : ", ");
    return os << ']';
}

template<class T>
ostream &operator<<(ostream &os, const set<T> &st) {
    os << '{';
    auto it = st.begin();
    while (it != st.end()) {
        os << (it == st.begin() ? "" : ", ") << *it;
        it++;
    }
    return os << '}';
}

template<class T>
ostream &operator<<(ostream &os, const multiset<T> &st) {
    os << '{';
    auto it = st.begin();
    while (it != st.end()) {
        os << (it == st.begin() ? "" : ", ") << *it;
        it++;
    }
    return os << '}';
}

template<class T, class U>
ostream &operator<<(ostream &os, const map<T, U> &mp) {
    os << '{';
    auto it = mp.begin();
    while (it != mp.end()) {
        os << (it == mp.begin() ? "" : ", ") << *it;
        it++;
    }
    return os << '}';
}

template<class T>
void vecout(const vector<T> &v, char div = '\n') {
    rep(i, v.size()) cout << v[i] << (i == int(v.size() - 1) ? '\n' : div);
}

template<class T>
bool constexpr chmin(T &a, T b) {
    if (a > b) {
        a = b;
        return true;
    }
    return false;
}

template<class T>
bool constexpr chmax(T &a, T b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}

void scan() {}

template<class Head, class... Tail>
void scan(Head &head, Tail &... tail) {
    cin >> head;
    scan(tail...);
}

template<class T>
void print(const T &t) { cout << t << '\n'; }

template<class Head, class... Tail>
void print(const Head &head, const Tail &... tail) {
    cout << head << ' ';
    print(tail...);
}

template<class T>
vector<T> &operator+=(vector<T> &v, T x) {
    for (T &t: v) t += x;
    return v;
}

template<class T>
vector<T> &operator-=(vector<T> &v, T x) {
    for (T &t: v) t -= x;
    return v;
}

template<class T>
vector<T> &operator*=(vector<T> &v, T x) {
    for (T &t: v) t *= x;
    return v;
}

template<class T>
vector<T> &operator/=(vector<T> &v, T x) {
    for (T &t: v) t /= x;
    return v;
}

struct Init_io {
    Init_io() {
        ios::sync_with_stdio(false);
        cin.tie(nullptr);
        cout.tie(nullptr);
        cout << boolalpha << fixed << setprecision(15);
        cerr << boolalpha << fixed << setprecision(15);
    }
} init_io;

const string yes[] = {"no", "yes"};
const string Yes[] = {"No", "Yes"};
const string YES[] = {"NO", "YES"};
const int inf = 1001001001;
const ll linf = 1001001001001001001;

void rearrange(const vi &) {}

template<class T, class... Tail>
void rearrange(const vi &ord, vector<T> &head, Tail &...tail) {
    assert(ord.size() == head.size());
    vector<T> ori = head;
    rep(i, ord.size()) head[i] = ori[ord[i]];
    rearrange(ord, tail...);
}

template<class T, class... Tail>
void sort_by(vector<T> &head, Tail &... tail) {
    vi ord(head.size());
    iota(all(ord), 0);
    sort(all(ord), [&](int i, int j) { return head[i] < head[j]; });
    rearrange(ord, head, tail...);
}

bool in_rect(int i, int j, int h, int w) {
    return 0 <= i and i < h and 0 <= j and j < w;
}

template<class T>
constexpr vector<T> pow_table(int n, T base) {
    vector<T> res(n, 1);
    rep(i, n - 1) res[i + 1] = res[i] * base;
    return res;
}

template<class T, class S>
vector<T> cumsum(const vector<S> &v, bool shift_one = true) {
    int n = v.size();
    vector<T> res;
    if (shift_one) {
        res.resize(n + 1);
        rep(i, n) res[i + 1] = res[i] + v[i];
    } else {
        res.resize(n);
        if (n) {
            res[0] = v[0];
            rep(i, 1, n) res[i] = res[i - 1] + v[i];
        }
    }
    return res;
}

vvi graph(int n, int m, bool directed = false, int origin = 1) {
    vvi G(n);
    rep(_, m) {
        INT(u, v);
        u -= origin, v -= origin;
        G[u].pb(v);
        if (!directed) G[v].pb(u);
    }
    return G;
}

template<class T>
vector<vector<pair<int, T>>> weighted_graph(int n, int m, bool directed = false, int origin = 1) {
    vector<vector<pair<int, T>>> G(n);
    rep(_, m) {
        int u, v;
        T w;
        scan(u, v, w);
        u -= origin, v -= origin;
        G[u].eb(v, w);
        if (!directed) G[v].eb(u, w);
    }
    return G;
}

// Decomposition of Strongly Connected Components
class SCC {
    int n;
    vvi G, rG;
    vi ord, bel;
    vb used;
    
    void init() {
        rG.resize(n);
        rep(i, n) for (int j: G[i]) rG[j].pb(i);
        bel.resize(n);
        used.resize(n);
    }
    
    void dfs(int v) {
        used[v] = true;
        for (int u: G[v]) if (!used[u]) dfs(u);
        ord.pb(v);
    }
    
    void rdfs(int v, int k) {
        used[v] = true;
        bel[v] = k;
        for (int u: rG[v]) if (!used[u]) rdfs(u, k);
    }

public:
    // number of components
    int num;
    
    SCC(const vvi &G) : G(G) {
        n = G.size();
        init();
        used.assign(n, false);
        rep(i, n) if (!used[i]) dfs(i);
        used.assign(n, false);
        int k = 0;
        rrep(i, n) if (!used[ord[i]]) rdfs(ord[i], k++);
        num = k;
    }
    
    // belonging components(topological order)
    int get(int i) { return bel[i]; }
};

// ref : https://lorent-kyopro.hatenablog.com/entry/2020/07/24/170656
struct range_edge_graph {
    int n;
    vector<vector<int>> g;
    
    range_edge_graph(int n) : n(n) {
        g.resize(4 * n);
        for (int i = 1; i < n; ++i) {
            int cl = i << 1 | 0, cr = i << 1 | 1;
            g[i].push_back(cl);
            g[i].push_back(cr);
            g[cl + 2 * n].push_back(i + 2 * n);
            g[cr + 2 * n].push_back(i + 2 * n);
        }
        for (int i = n; i < 2 * n; ++i) g[i].push_back(i + 2 * n);
    }
    
    // from [l1, r1) to [l2, r2)
    void add_edge(int l1, int r1, int l2, int r2) {
        int idx = g.size();
        for (l1 += n, r1 += n; l1 < r1; l1 >>= 1, r1 >>= 1) {
            if (l1 & 1) g[l1 + 2 * n].push_back(idx), l1++;
            if (r1 & 1) --r1, g[r1 + 2 * n].push_back(idx);
        }
        vector<int> node;
        for (l2 += n, r2 += n; l2 < r2; l2 >>= 1, r2 >>= 1) {
            if (l2 & 1) node.push_back(l2++);
            if (r2 & 1) node.push_back(--r2);
        }
        g.push_back(node);
    }
};

void solve() {
    INT(n, q);
    range_edge_graph rg(3 * n);
    rep(_, q) {
        INT(a, b, c, d);
        --a, --c;
        rg.add_edge(a, b, c, d);
    }
    debug(SZ(rg.g));
    SCC scc(rg.g);
    int sz = scc.num;
    vi w(sz);
    vvi G(sz), rG(sz);
    rep(i, SZ(rg.g)) {
        int bi = scc.get(i);
        for (int j: rg.g[i]) {
            int bj = scc.get(j);
            if (bi == bj) continue;
            assert(bi < bj);
            G[bi].pb(bj);
            rG[bj].pb(bi);
        }
        if (3 * n <= i and i < 6 * n) ++w[bi];
    }
    int id = -1;
    rep(i, sz) if (w[i] >= n + 2) {
            id = i;
            break;
        }
    vb use(sz);
    if (id == -1) {
        int sum = 0;
        rrep(i, sz) {
            use[i] = true;
            sum += w[i];
            assert(sum <= 2 * n);
            if (sum >= n) break;
        }
    } else {
        int sum = 0;
        vb dp(sz);
        dp[id] = true;
        rep(i, sz) {
            if (!dp[i]) continue;
            sum += w[i];
            for (int j: G[i]) dp[j] = true;
        }
        if (sum <= 2 * n) {
            use = dp;
        } else {
            sum = 0;
            dp.assign(sz, false);
            dp[id] = true;
            rrep(i, sz) {
                if (!dp[i]) continue;
                sum += w[i];
                for (int j: rG[i]) dp[j] = true;
            }
            if (sum > 2 * n) {
                print("NIE");
                return;
            }
            rep(i, sz) dp[i] = !dp[i];
            use = dp;
        }
    }
    print("TAK");
    string ans(3 * n, 'R');
    rep(i, 3 * n) if (use[scc.get(3 * n + i)]) ans[i] = 'F';
    print(ans);
}

int main() {
    int t;
    cin >> t;
    rep(i, t) solve();
}