# include <bits/stdc++.h>
using namespace std;
int T,n,m,cnt,ecnt,go[3000010],adj[1200010],nxt[3000010],dfncnt,dfn[1200010],low[1200010],ins[1200010],wo[1200010],d[1200010],scccnt,scc[1200010],sccwo[1200010],tpcnt,tp[1200010],ans[1200010],vis[1200010];
pair<int,int> to[1200010];
stack<int> s;
queue<int> q;
vector<int> ok,fed[1200010],sed[1200010],sc[1200010];
struct node { int a,b,c,d;} op[100010];
void add_(int u,int v) { go[++ecnt]=v, nxt[ecnt]=adj[u], adj[u]=ecnt;}
void build_(int k,int l,int r,int opt) {
    if (opt==1) to[k].first=++cnt;
    else to[k].second=++cnt;
    if (k!=1) {
        if (opt==1) add_(to[k].first,to[k/2].first);
        else add_(to[k/2].second,to[k].second);
    }
    if (l==r) {
        if (opt==1) add_(l,to[k].first);
        else add_(to[k].second,l);
        return;
    }
    int mid=(l+r)>>1;
    build_(k<<1,l,mid,opt), build_(k<<1|1,mid+1,r,opt);
}
void turn_add_(int k,int l,int r,int lpos,int rpos,int opt,int kl) {
    if (lpos<=l&&r<=rpos) {
        if (opt==1) add_(to[k].first,kl);
        else add_(kl,to[k].second);
        return;
    }
    int mid=(l+r)>>1;
    if (lpos<=mid) turn_add_(k<<1,l,mid,lpos,rpos,opt,kl);
    if (mid<rpos) turn_add_(k<<1|1,mid+1,r,lpos,rpos,opt,kl);
}
void tarjan_(int x) {
    s.push(x), ins[x]=1, low[x]=dfn[x]=++dfncnt;
    for (int i=adj[x];i;i=nxt[i]) 
        if (!dfn[go[i]]) tarjan_(go[i]), low[x]=min(low[x],low[go[i]]);
        else if (ins[go[i]]) low[x]=min(low[x],dfn[go[i]]);
    if (low[x]!=dfn[x]) return;
    scccnt++;
    while (!s.empty()&&dfn[s.top()]>=dfn[x]) scc[s.top()]=scccnt, sc[scccnt].push_back(s.top()), sccwo[scccnt]+=wo[s.top()], ins[s.top()]=0, s.pop();
}
int main() {
    // freopen("in.in","r",stdin);
    // freopen("out.out","w",stdout);
    
    scanf("%d",&T);

    while (T--) {
        scanf("%d%d",&n,&m);
        for (int i=1;i<=m;i++) scanf("%d%d%d%d",&op[i].a,&op[i].b,&op[i].c,&op[i].d);

        cnt=3*n;
        build_(1,1,3*n,1), build_(1,1,3*n,2);
        for (int i=1;i<=m;i++) turn_add_(1,1,3*n,op[i].a,op[i].b,1,cnt+i), turn_add_(1,1,3*n,op[i].c,op[i].d,2,cnt+i);

        for (int i=1;i<=3*n;i++) wo[i]=1;
        for (int i=1;i<=cnt+m;i++) if (!dfn[i]) tarjan_(i);
        for (int i=1;i<=cnt+m;i++) for (int j=adj[i];j;j=nxt[j]) if (scc[i]!=scc[go[j]]) fed[scc[i]].push_back(scc[go[j]]), sed[scc[go[j]]].push_back(scc[i]), d[scc[go[j]]]++;

        for (int i=1;i<=scccnt;i++) if (sccwo[i]>=n) {
            vector<int> v; 
            ok.clear();
            for (int j=1;j<=scccnt;j++) vis[j]=0;
            v.push_back(i), vis[i]=1;
            while (!v.empty()) {
                int e=v.back(); v.pop_back();
                for (auto o : sc[e]) if (wo[o]) ok.push_back(o);
                for (auto o : fed[e]) if (!vis[o]) vis[o]=1, v.push_back(o);
            }
            if ((int)ok.size()<=2*n) {
                assert((int)ok.size()>=n);
                for (auto o : ok) ans[o]=1;
                goto pos;
            }
            ok.clear();
            for (int j=1;j<=scccnt;j++) vis[j]=0;
            v.push_back(i), vis[i]=1;
            while (!v.empty()) {
                int e=v.back(); v.pop_back();
                for (auto o : sc[e]) if (wo[o]) ok.push_back(o);
                for (auto o : sed[e]) if (!vis[o]) vis[o]=1, v.push_back(o);
            }
            if ((int)ok.size()<=2*n) {
                assert((int)ok.size()>=n);
                for (int j=1;j<=3*n;j++) ans[j]=1;
                for (auto o : ok) ans[o]=0;
                goto pos;
            }
        }

        for (int i=1;i<=scccnt;i++) if (!d[i]) q.push(i);
        while (!q.empty()) {
            int e=q.front(); q.pop();
            tp[++tpcnt]=e;
            for (auto o : fed[e]) {
                d[o]--;
                if (!d[o]) q.push(o);
            }
        }
        ok.clear();
        for (int i=1;i<=scccnt;i++) {
            int e=tp[i];
            for (auto o : sc[e]) if (wo[o]) ok.push_back(o);
            if ((int)ok.size()>=n&&(int)ok.size()<=2*n) {
                assert((int)ok.size()>=n);
                for (int j=1;j<=3*n;j++) ans[j]=1;
                for (auto o : ok) ans[o]=0;
                goto pos;
            }
        }

        printf("NIE\n");
        goto pos2;

pos:;
        printf("TAK\n");
        for (int i=1;i<=3*n;i++) printf(ans[i] ? "F" : "R");
        printf("\n");

pos2:;
        for (int i=1;i<=cnt+m;i++) adj[i]=dfn[i]=low[i]=ins[i]=wo[i]=ans[i]=0;
        for (int i=1;i<=scccnt;i++) sccwo[i]=tp[i]=d[i]=0, fed[i].clear(), sed[i].clear(), sc[i].clear();
        scccnt=dfncnt=tpcnt=cnt=ecnt=0;
    }

    return 0;
}