// 2023 IUSB Programming Competition
// Round 2 Problem 2
// Word Search
// Solution by Liguo Yu

#include <iostream>
#include <string>
using namespace std;

bool check(char ** array, int x, int y, int m, int n, string word);

int main()
{
  string word;
  int x, y;
  cin >> word;
  cin >> x;
  cin >> y;
  
  char ** array = new char *[x];
  for (int i=0; i<x; i++)
  {
      array[i] = new char[y];
  }

  for (int i=0; i<x; i++)
  {
    for(int j=0; j<y; j++)
    {
      string word;
      cin >> word;
      array[i][j] = word.at(0);
    }
  }
        
  bool found = false;
        
  for (int i=0; i<x; i++)
  {
    for(int j=0; j<y; j++)
    {
      if(check(array, x, y, i, j, word) == true)
        found = true;
    }
  }       
  
  if(found == false) cout << "no";
  else cout << "yes";
}

//for every position (m, n), check eight directions
bool check(char ** array, int x, int y, int m, int n, string word)
{
  //horizontally  forward
  string s = "";
  for (int j=n; j<y; j++)
  {
    s = s + array[m][j];
  }
  if(s.find(word)!= string::npos) return true;   
        
  //horizontally  backward
  s = "";
  for (int j=n; j>=0; j--)
  {
    s = s + array[m][j];
  }          
  if(s.find(word)!= string::npos) return true; 
               
  //vertically downward
  s = "";
  for (int i=m; i<x; i++)
  {
    s = s + array[i][n];
  }
  if(s.find(word)!= string::npos) return true;

  //vertically upward
  s = "";
  for (int i=m; i>=0; i--)
  {
    s = s + array[i][n];
  }
  if(s.find(word)!= string::npos) return true;
        
  // diagonally: /up
  s = "";
  int i = m;
  int j = n;
  while(i >= 0 && j < y)
  {
    s = s + array[i][j];
    i--;
    j++;
  }
  if(s.find(word)!= string::npos) return true;
        
  // diagonally: /down
  s = "";
  i = m;
  j = n;
  while(i < x && j >= 0)
  {
    s = s + array[i][j];
    i++;
    j--;
  }
  if(s.find(word)!= string::npos) return true;
        
  // diagonally: up
  s = "";
  i = m;
  j = n;
  while(i >= 0 && j >= 0)
  {
    s = s + array[i][j];
    i--;
    j--;
  }
  if(s.find(word)!= string::npos) return true;
        
  // diagonally: \down
  s = "";
  i = m;
  j = n;
  while(i < x && j < y)
  {
    s = s + array[i][j];
    i++;
    j++;
  }
  if(s.find(word)!= string::npos) return true;
        
  return false;
}