//#define _GLIBCXX_DEBUG

//#pragma GCC target("avx2")
//#pragma GCC optimize("O3")
//#pragma GCC optimize("unroll-loops")

#include<bits/stdc++.h>
using namespace std;


#ifdef LOCAL
#include <debug_print.hpp>
#define OUT(...) debug_print::multi_print(#__VA_ARGS__, __VA_ARGS__)
#else
#define OUT(...) (static_cast<void>(0))
#endif

#define endl '\n'
#define lfs cout<<fixed<<setprecision(15)
#define ALL(a)  (a).begin(),(a).end()
#define ALLR(a)  (a).rbegin(),(a).rend()
#define UNIQUE(a) (a).erase(unique((a).begin(),(a).end()),(a).end())
#define spa << " " <<
#define fi first
#define se second
#define MP make_pair
#define MT make_tuple
#define PB push_back
#define EB emplace_back
#define rep(i,n,m) for(ll i = (n); i < (ll)(m); i++)
#define rrep(i,n,m) for(ll i = (ll)(m) - 1; i >= (ll)(n); i--)
using ll = long long;
using ld = long double;
const ll MOD1 = 1e9+7;
const ll MOD9 = 998244353;
const ll INF = 1e18;
using P = pair<ll, ll>;
template<typename T> using PQ = priority_queue<T>;
template<typename T> using QP = priority_queue<T,vector<T>,greater<T>>;
template<typename T1, typename T2>bool chmin(T1 &a,T2 b){if(a>b){a=b;return true;}else return false;}
template<typename T1, typename T2>bool chmax(T1 &a,T2 b){if(a<b){a=b;return true;}else return false;}
ll median(ll a,ll b, ll c){return a+b+c-max({a,b,c})-min({a,b,c});}
void ans1(bool x){if(x) cout<<"Yes"<<endl;else cout<<"No"<<endl;}
void ans2(bool x){if(x) cout<<"YES"<<endl;else cout<<"NO"<<endl;}
void ans3(bool x){if(x) cout<<"Yay!"<<endl;else cout<<":("<<endl;}
template<typename T1,typename T2>void ans(bool x,T1 y,T2 z){if(x)cout<<y<<endl;else cout<<z<<endl;}  
template<typename T1,typename T2,typename T3>void anss(T1 x,T2 y,T3 z){ans(x!=y,x,z);};  
template<typename T>void debug(const T &v,ll h,ll w,string sv=" "){for(ll i=0;i<h;i++){cout<<v[i][0];for(ll j=1;j<w;j++)cout<<sv<<v[i][j];cout<<endl;}};
template<typename T>void debug(const T &v,ll n,string sv=" "){if(n!=0)cout<<v[0];for(ll i=1;i<n;i++)cout<<sv<<v[i];cout<<endl;};
template<typename T>void debug(const vector<T>&v){debug(v,v.size());}
template<typename T>void debug(const vector<vector<T>>&v){for(auto &vv:v)debug(vv,vv.size());}
template<typename T>void debug(stack<T> st){while(!st.empty()){cout<<st.top()<<" ";st.pop();}cout<<endl;}
template<typename T>void debug(queue<T> st){while(!st.empty()){cout<<st.front()<<" ";st.pop();}cout<<endl;}
template<typename T>void debug(deque<T> st){while(!st.empty()){cout<<st.front()<<" ";st.pop_front();}cout<<endl;}
template<typename T>void debug(PQ<T> st){while(!st.empty()){cout<<st.top()<<" ";st.pop();}cout<<endl;}
template<typename T>void debug(QP<T> st){while(!st.empty()){cout<<st.top()<<" ";st.pop();}cout<<endl;}
template<typename T>void debug(const set<T>&v){for(auto z:v)cout<<z<<" ";cout<<endl;}
template<typename T>void debug(const multiset<T>&v){for(auto z:v)cout<<z<<" ";cout<<endl;}
template<typename T,size_t size>void debug(const array<T, size> &a){for(auto z:a)cout<<z<<" ";cout<<endl;}
template<typename T,typename V>void debug(const map<T,V>&v){for(auto z:v)cout<<"["<<z.first<<"]="<<z.second<<",";cout<<endl;}
template<typename T>vector<vector<T>>vec(ll x, ll y, T w){vector<vector<T>>v(x,vector<T>(y,w));return v;}
vector<ll>dx={1,-1,0,0,1,1,-1,-1};vector<ll>dy={0,0,1,-1,1,-1,1,-1};
template<typename T>vector<T> make_v(size_t a,T b){return vector<T>(a,b);}
template<typename... Ts>auto make_v(size_t a,Ts... ts){return vector<decltype(make_v(ts...))>(a,make_v(ts...));}
template<typename T1, typename T2>ostream &operator<<(ostream &os, const pair<T1, T2>&p){return os << "(" << p.first << "," << p.second << ")";}
template<typename T>ostream &operator<<(ostream &os, const vector<T> &v){os<<"[";for(auto &z:v)os << z << ",";os<<"]"; return os;}
template<typename T>void rearrange(vector<int>&ord, vector<T>&v){
  auto tmp = v;
  for(int i=0;i<tmp.size();i++)v[i] = tmp[ord[i]];
}
template<typename Head, typename... Tail>void rearrange(vector<int>&ord,Head&& head, Tail&&... tail){
  rearrange(ord, head);
  rearrange(ord, tail...);
}
template<typename T> vector<int> ascend(const vector<T>&v){
  vector<int>ord(v.size());iota(ord.begin(),ord.end(),0);
  sort(ord.begin(),ord.end(),[&](int i,int j){return make_pair(v[i],i)<make_pair(v[j],j);});
  return ord;
}
template<typename T> vector<int> descend(const vector<T>&v){
  vector<int>ord(v.size());iota(ord.begin(),ord.end(),0);
  sort(ord.begin(),ord.end(),[&](int i,int j){return make_pair(v[i],-i)>make_pair(v[j],-j);});
  return ord;
}
template<typename T> vector<T> inv_perm(const vector<T>&ord){
  vector<T>inv(ord.size());
  for(int i=0;i<ord.size();i++)inv[ord[i]] = i;
  return inv;
}
ll FLOOR(ll n,ll div){assert(div>0);return n>=0?n/div:(n-div+1)/div;}
ll CEIL(ll n,ll div){assert(div>0);return n>=0?(n+div-1)/div:n/div;}
ll digitsum(ll n){ll ret=0;while(n){ret+=n%10;n/=10;}return ret;}
ll modulo(ll n,ll d){return (n%d+d)%d;};
template<typename T>T min(const vector<T>&v){return *min_element(v.begin(),v.end());}
template<typename T>T max(const vector<T>&v){return *max_element(v.begin(),v.end());}
template<typename T>T acc(const vector<T>&v){return accumulate(v.begin(),v.end(),T(0));};
template<typename T>T reverse(const T &v){return T(v.rbegin(),v.rend());};
//mt19937 mt(chrono::steady_clock::now().time_since_epoch().count());
int popcount(ll x){return __builtin_popcountll(x);};
int poplow(ll x){return __builtin_ctzll(x);};
int pophigh(ll x){return 63 - __builtin_clzll(x);};
template<typename T>T poll(queue<T> &q){auto ret=q.front();q.pop();return ret;};
template<typename T>T poll(priority_queue<T> &q){auto ret=q.top();q.pop();return ret;};
template<typename T>T poll(QP<T> &q){auto ret=q.top();q.pop();return ret;};
template<typename T>T poll(stack<T> &s){auto ret=s.top();s.pop();return ret;};
ll MULT(ll x,ll y){if(LLONG_MAX/x<=y)return LLONG_MAX;return x*y;}
ll POW2(ll x, ll k){ll ret=1,mul=x;while(k){if(mul==LLONG_MAX)return LLONG_MAX;if(k&1)ret=MULT(ret,mul);mul=MULT(mul,mul);k>>=1;}return ret;}
ll POW(ll x, ll k){ll ret=1;for(int i=0;i<k;i++){if(LLONG_MAX/x<=ret)return LLONG_MAX;ret*=x;}return ret;}
namespace converter{
  int dict[500];
  const string lower="abcdefghijklmnopqrstuvwxyz";
  const string upper="ABCDEFGHIJKLMNOPQRSTUVWXYZ";
  const string digit="0123456789";
  const string digit1="123456789";
  void regi_str(const string &t){
    for(int i=0;i<t.size();i++){
      dict[t[i]]=i;
    }
  }
  void regi_int(const string &t){
    for(int i=0;i<t.size();i++){
      dict[i]=t[i];
    }
  }
  vector<int>to_int(const string &s,const string &t){
    regi_str(t);
    vector<int>ret(s.size());
    for(int i=0;i<s.size();i++){
      ret[i]=dict[s[i]];
    }
    return ret;
  }
  vector<int>to_int(const string &s){
    auto t=s;
    sort(t.begin(),t.end());
    t.erase(unique(t.begin(),t.end()),t.end());
    return to_int(s,t);
  }
  
  vector<vector<int>>to_int(const vector<string>&s,const string &t){
    regi_str(t);
    vector<vector<int>>ret(s.size(),vector<int>(s[0].size()));
    for(int i=0;i<s.size();i++){
      for(int j=0;j<s[0].size();j++){
        ret[i][j]=dict[s[i][j]];
      }
    }
    return ret;
  }
  vector<vector<int>>to_int(const vector<string>&s){
    string t;
    for(int i=0;i<s.size();i++){
      t+=s[i];
    }
    sort(t.begin(),t.end());t.erase(unique(t.begin(),t.end()),t.end());
    return to_int(s,t);
  }
  string to_str(const vector<int>&s,const string &t){
    regi_int(t);
    string ret;
    for(auto z:s)ret+=dict[z];
    return ret;
  }
  vector<string> to_str(const vector<vector<int>>&s,const string &t){
    regi_int(t);
    vector<string>ret(s.size());
    for(int i=0;i<s.size();i++){
      for(auto z:s[i])ret[i]+=dict[z];
    }
    return ret;
  }
}
template< typename T = int >
struct edge {
  int to;
  T cost;
  int id;
  edge():to(-1),id(-1){};
  edge(int to, T cost = 1, int id = -1):to(to), cost(cost), id(id){}
  operator int() const { return to; }
};

template<typename T>
using Graph = vector<vector<edge<T>>>;
template<typename T>
Graph<T>revgraph(const Graph<T> &g){
  Graph<T>ret(g.size());
  for(int i=0;i<g.size();i++){
    for(auto e:g[i]){
      int to = e.to;
      e.to = i;
      ret[to].push_back(e);
    }
  }
  return ret;
}
template<typename T>
Graph<T> readGraph(int n,int m,int indexed=1,bool directed=false,bool weighted=false){
  Graph<T> ret(n);
  for(int es = 0; es < m; es++){
    int u,v;
    T w=1;
    cin>>u>>v;u-=indexed,v-=indexed;
    if(weighted)cin>>w;
    ret[u].emplace_back(v,w,es);
    if(!directed)ret[v].emplace_back(u,w,es);
  }
  return ret;
}
template<typename T>
Graph<T> readParent(int n,int indexed=1,bool directed=true){
  Graph<T>ret(n);
  for(int i=1;i<n;i++){
    int p;cin>>p;
    p-=indexed;
    ret[p].emplace_back(i);
    if(!directed)ret[i].emplace_back(p);
  }
  return ret;
}
//無向オイラーパス:次数が奇数の頂点が2個
//無向オイラー閉路:全ての頂点の次数が偶数
//有向オイラーパス:入次数-出次数が1と-1が一個ずつ、他は0
//有向オイラー閉路:全ての頂点で入次数=出次数
//↑の条件を確認すること(作れないのに作ってしまう場合がある)
template<typename T>
vector<edge<T>> euler_path(int s,Graph<T>&g, int edge_num){
  vector<bool>used(edge_num);
  vector<int>idx(g.size());
  vector<edge<T>>ret;
  stack<edge<T>>st;
  int now=s;
  while(1){
    while(idx[now]<g[now].size()&&used[g[now][idx[now]].id])idx[now]++;
    if(idx[now]==g[now].size()){
      if(st.empty())break;
      ret.push_back(st.top());
      st.pop();
      if(st.empty())now=s;
      else now=st.top().to;
    }
    else{
      st.push(g[now][idx[now]]);
      used[g[now][idx[now]].id]=true;
      now=g[now][idx[now]].to;
    }
  }
  reverse(ret.begin(),ret.end());
  if(ret.size()==edge_num)return ret;
  else return vector<edge<T>>();
}
using ul = unsigned long long;
template<ll mod>
struct RollingHash{
  vector<ul> hash,p;
  const ul positivizer = mod * 4;
  ul base;
  RollingHash(string s, ul b){
    ul n = (ul)s.size();
    base = b;
    hash.assign(n+1,0);
    p.assign(n+1,1);
    for(ll i=0;i<n;i++){
      hash[i+1]=calcmod(mul(hash[i],base)+s[i]);
      p[i+1]=mul(p[i],base);
    }
  }
  ul get(ll l, ll r){ //[l,r)
    return calcmod(hash[r] + positivizer - mul(hash[l],p[r-l]));
  }
  ul mul(ul a, ul b){
    ul au = a >> 31;
    ul ad = a & (1UL << 31) - 1;
    ul bu = b >> 31;
    ul bd = b & (1UL << 31) - 1;
    ul mid = ad * bu + au * bd;
    ul midu = mid >> 30;
    ul midd = mid & (1UL << 30) - 1;
    return calcmod(au * bu * 2 + midu + (midd << 31) + ad * bd);
  }
  ul calcmod(ul val){
    val = (val & mod) + (val >> 61);
    if(val >= mod) val -= mod;
    return val;
  }
  ul merge(ul x,ul y, ll leny){
    return calcmod(mul(x,p[leny])+y);
  }
};
struct RandomNumberGenerator {
  mt19937_64 mt;

  RandomNumberGenerator() : mt(chrono::steady_clock::now().time_since_epoch().count()) {}

  ll operator()(ll a, ll b) { // [a, b)
    uniform_int_distribution< long long > dist(a, b - 1);
    return dist(mt);
  }

  ll operator()(ll b) { // [0, b)
    return (*this)(0, b);
  }
};
RandomNumberGenerator rng;
unsigned long long base = rng(100000,50000000);
const unsigned long long tmp_mod = (1ULL << 61) - 1;
using RH = RollingHash<tmp_mod>;

template<typename T>
struct Compress{
	vector<T>v;
	Compress(){
	}
	Compress(const vector<T>&input){
		add(input);
    build();
	}
  template<typename... Args>
  Compress(const vector<T> &head,const Args& ...input){
    add(head, input...);
    build();
  }
  template<typename... Args>
  Compress(const T &head,const Args& ...input){
    add(head, input...);
    build();
  }
  void build(){
		sort(v.begin(), v.end());
    v.erase(unique(v.begin(),v.end()),v.end());
  }
	void add(const vector<T>&add){
		v.insert(v.end(),add.begin(), add.end());
	}
  template<typename Head, typename ...Tail>
  void add(const Head& head,const Tail& ...tail){
    add(head);
    add(tail...);
  }
  void add(T val){
    v.push_back(val);
  }
  int next(T val){
    return lower_bound(v.begin(), v.end(), val) - v.begin();
  }
  int prev(T val){
    return upper_bound(v.begin(), v.end(), val) - v.begin() - 1;
  }
  bool exist(T val){
    return binary_search(v.begin(), v.end(), val);
  }
  T val(int x){
    return v[x];
  }
  vector<int>compress(const vector<T>&input){
    vector<int>ret(input.size());
    for(int i=0;i<input.size();i++)ret[i]=next(input[i]);
    return ret;
  }
  int operator[](T val){
    return next(val);
  }
  int size(){
    return v.size();
  }
};

void solve(){
  ll n,m;cin>>n>>m;
  vector<string>a(n),b(n);
  rep(i,0,n)cin>>a[i];
  rep(i,0,n)cin>>b[i];
  vector<RH>ra,rb;
  rep(i,0,n){
    ra.EB(a[i],base);
    rb.EB(b[i],base);
  }
  rep(d,0,m){
    vector<ul>in,out;
    rep(i,0,n){
      auto apre=ra[i].get(0,d);
      auto asuf=ra[i].get(d,m)+(1ULL<<62);
      in.PB(apre);
      out.PB(asuf);
    }
    rep(i,0,n){
      auto bpre=rb[i].get(0,m-d)+(1ULL<<62);
      auto bsuf=rb[i].get(m-d,m);
      in.PB(bpre);
      out.PB(bsuf);
    }
    Compress mp(in,out);
    Graph<ll>g(mp.size());
    vector<int>din(mp.size());
    rep(i,0,2*n){
      g[mp[in[i]]].EB(mp[out[i]],1,i);
    }
    rep(i,0,g.size()){
      for(auto to:g[i])din[to]++;
    }
    bool sw=true;
    rep(i,0,g.size()){
      if(g[i].size()!=din[i])sw=false;
    }
    if(!sw)continue;
    auto path=euler_path(0,g,2*n);
    if(path.empty())continue;
    vector<int>p,q;
    for(auto e:path){
      if(e.id<n)p.PB(e.id+1);
      else q.PB(e.id-n+1);
    }
    debug(p);
    debug(q);
    return;
  }
  cout<<-1<<endl;
}
int main(){
  cin.tie(nullptr);
  ios_base::sync_with_stdio(false);
  ll res=0,buf=0;
  bool judge = true;
  ll t;cin>>t;
  while(t--){
    solve();
  }
  return 0;
}