#include "../../common.cpp"
#include <boost/graph/push_relabel_max_flow.hpp>
#include <boost/graph/graphviz.hpp>

// Graph Type with nested interior edge properties for flow algorithms
typedef boost::adjacency_list_traits<boost::vecS, boost::vecS, boost::directedS> traits;
typedef boost::adjacency_list<boost::vecS, boost::vecS, boost::directedS, boost::no_property,
  boost::property<boost::edge_capacity_t, int,
                  boost::property<boost::edge_residual_capacity_t, int,
                                  boost::property<boost::edge_reverse_t, traits::edge_descriptor>>>> graph;
typedef traits::vertex_descriptor vertex_desc;
typedef traits::edge_descriptor edge_desc;

class edge_adder {
  graph &G;
public:
  explicit edge_adder(graph &G) : G(G) {}
  void add_edge(int from, int to, int capacity) {
    auto c_map = boost::get(boost::edge_capacity, G);
    auto r_map = boost::get(boost::edge_reverse, G);
    const auto e = boost::add_edge(from, to, G).first;
    const auto rev_e = boost::add_edge(to, from, G).first;
    c_map[e] = capacity;
    c_map[rev_e] = 0; // reverse edge has no capacity!
    r_map[e] = rev_e;
    r_map[rev_e] = e;
  }
};

int main(){
  setup();

  auto t = read1<int>();
  while(0 < t--){
    auto h = read1<int>();
    auto w = read1<int>();
    auto note = read1<std::string>();
    int n = note.size();
    graph G(2+n+h*w);
    edge_adder adder(G);
    
    int counter = 2;
    // Edge to target
    for(int i=0; i<n; ++i){
      adder.add_edge(counter++, 1, 1);
    }

    // Edge from source
    for(int i=0; i<h*w; ++i){
      adder.add_edge(0, counter++, 1);
    }

    // Front vertex
    int off = n+2;
    for(int i=0; i<h; ++i){
      auto line = read1<std::string>();
      for(int j=0; j<w; ++j){
        char c = line[j];
        for(int k=0; k<n; ++k){
          if(note[k] == c)
            adder.add_edge(off+i*w+j, k+2, 1);
        }
      }
    }
    
    // Back vertex
    for(int i=0; i<h; ++i){
      auto line = read1<std::string>();
      for(int j=0; j<w; ++j){
        char c = line[j];
        for(int k=0; k<n; ++k){
          if(note[k] == c)
            adder.add_edge(off+i*w+j, k+2, 1);
        }
      }
    }
    
    // if(t==0){
    //   boost::write_graphviz(std::cout, G);
    //   return 0;
    // }

    auto flow = boost::push_relabel_max_flow(G, boost::vertex(0, G), boost::vertex(1, G));
    std::cout << ((flow == n)? "Yes" : "No") << '\n';
  }
}